From d59a62e6208cdc21f3ba189bee3e821541ce1f14 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Wed, 29 Apr 2026 18:31:34 -0400
Subject: [PATCH 01/24] Simplify implementation

---
 README.md                         | 19 +++---
 examples/mic.js                   |  9 ++-
 index.d.ts                        | 24 +++++++-
 index.js                          |  1 +
 polyfill.js                       | 97 +------------------------------
 src/MediaStream.js                | 79 +++++++++++++++++++++++++
 src/MediaStreamAudioSourceNode.js | 60 +++----------------
 test/MediaStreamNodes.test.js     | 36 ++++++++----
 test/polyfill.test.js             | 20 -------
 9 files changed, 154 insertions(+), 191 deletions(-)
 create mode 100644 src/MediaStream.js

diff --git a/README.md b/README.md
index 47f1209..e8e5cb3 100644
--- a/README.md
+++ b/README.md
@@ -94,7 +94,7 @@ Beyond the spec, for Node.js. Not portable to browsers.
 - **`addModule(fn)`** — register a processor via callback instead of URL, no file needed
 - **`sinkId: stream`** — pipe PCM to any writable: `new AudioContext({ sinkId: process.stdout })` then `node synth.js | aplay -f cd`
 - **`numberOfChannels`, `bitDepth`** — control output format in the constructor
-- **`navigator.mediaDevices.getUserMedia({ audio: true })`** — browser-parity microphone capture in Node. Load `web-audio-api/polyfill` and install [`audio-mic`](https://github.com/audiojs/audio-mic); browser mic code then runs verbatim. See the [mic FAQ](#how-do-i-capture-audio-from-the-microphone).
+- **`MediaStreamTrack`, `MediaStream`** — exposed from `web-audio-api`. `MediaStreamTrack` has a `pushData(chunk, options)` method to feed audio (e.g. from a microphone). See the [mic FAQ](#how-do-i-capture-audio-from-the-microphone).
 
 ## FAQ
 
@@ -147,35 +147,36 @@ const buffer = await ctx.decodeAudioData(readFileSync('track.mp3'))
 WAV, MP3, FLAC, OGG, AAC via [audio-decode](https://github.com/audiojs/audio-decode).
 </dd>
 
-<dt>How do I capture audio from the microphone?</dt>
+<dt id="how-do-i-capture-audio-from-the-microphone">How do I capture audio from the microphone?</dt>
 <dd>
 
-In Node, pair [`audio-mic`](https://github.com/audiojs/audio-mic) with `MediaStreamAudioSourceNode.pushData()`:
+In Node, pair [`audio-mic`](https://github.com/audiojs/audio-mic) with `MediaStreamTrack.pushData()`:
 
 ```sh
 npm install audio-mic
 ```
 
 ```js
-import { AudioContext, MediaStreamAudioSourceNode } from 'web-audio-api'
+import { AudioContext, MediaStreamAudioSourceNode, MediaStreamTrack, MediaStream } from 'web-audio-api'
 import mic from 'audio-mic'
 
 const ctx = new AudioContext()
 await ctx.resume()
 
-const src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1, bitDepth: 16 })
+const track = new MediaStreamTrack('audio', 'mic', { channelCount: 1, sampleSize: 16, sampleRate: ctx.sampleRate })
+const stream = new MediaStream([track])
+
+const src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
 src.connect(ctx.destination) // live monitor
 
 const read = mic({ sampleRate: ctx.sampleRate, channels: 1, bitDepth: 16 })
 read((err, buf) => {
   if (err || !buf) return
-  src.pushData(buf, { channels: 1, bitDepth: 16 })
+  track.pushData(buf, { channels: 1, bitDepth: 16 })
 })
 ```
 
-`pushData()` accepts `Float32Array`, `Float32Array[]`, or interleaved 8/16/32-bit integer PCM buffers. Integer PCM conversion uses `pcm-convert`.
-
-With `web-audio-api/polyfill`, `navigator.mediaDevices.getUserMedia()` is also available and maps constraints to `audio-mic` options: `{ audio: { sampleRate, channelCount, sampleSize } }`.
+`track.pushData()` accepts `Float32Array`, `Float32Array[]`, or interleaved 8/16/32-bit integer PCM buffers. Integer PCM conversion uses `pcm-convert`.
 
 See [examples/mic.js](examples/mic.js) for a runnable demo with gain and VU meter. To record the graph to a buffer, use `OfflineAudioContext.startRendering()`. To capture live graph output as a stream, use `ctx.createMediaStreamDestination()`.
 </dd>
diff --git a/examples/mic.js b/examples/mic.js
index b89e5f3..26eb78e 100644
--- a/examples/mic.js
+++ b/examples/mic.js
@@ -5,7 +5,7 @@
 // Run: node examples/mic.js gain=0.8
 // Keys: space pause · + / - adjust gain · q quit
 
-import { AudioContext, MediaStreamAudioSourceNode } from 'web-audio-api'
+import { AudioContext, MediaStreamAudioSourceNode, MediaStream, MediaStreamTrack } from 'web-audio-api'
 import mic from 'audio-mic'
 import { args, keys, status, clearLine, pausedTag } from './_util.js'
 
@@ -18,7 +18,10 @@ let bitDepth = parseInt($('bit', '16'))
 const ctx = new AudioContext({ sampleRate })
 await ctx.resume()
 
-const src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: channels, bitDepth })
+const track = new MediaStreamTrack('audio', 'mic', { channelCount: channels, sampleSize: bitDepth, sampleRate })
+const stream = new MediaStream([track])
+
+const src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
 const gain = ctx.createGain()
 const analyser = ctx.createAnalyser()
 gain.gain.value = gainVal
@@ -28,7 +31,7 @@ src.connect(gain).connect(analyser).connect(ctx.destination)
 let read = mic({ sampleRate, channels, bitDepth })
 read((err, buf) => {
   if (err || !buf) return
-  src.pushData(buf, { channels, bitDepth })
+  track.pushData(buf, { channels, bitDepth })
 })
 
 let samples = new Float32Array(analyser.fftSize)
diff --git a/index.d.ts b/index.d.ts
index beae5a9..22ee1a4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -259,7 +259,6 @@ export class AudioWorkletProcessor {
 
 export class MediaStreamAudioSourceNode extends AudioNode {
   readonly mediaStream: any;
-  pushData(channelData: Float32Array | Float32Array[] | ArrayBuffer | ArrayBufferView, options?: { channels?: number; numberOfChannels?: number; bitDepth?: 8 | 16 | 32 }): void;
 }
 
 export class MediaStreamAudioDestinationNode extends AudioNode {
@@ -270,6 +269,29 @@ export class MediaElementAudioSourceNode extends AudioNode {
   readonly mediaElement: any;
 }
 
+export class MediaStreamTrack extends EventTarget {
+  readonly id: string;
+  readonly kind: string;
+  readonly label: string;
+  enabled: boolean;
+  readonly readyState: 'live' | 'ended';
+  stop(): void;
+  clone(): MediaStreamTrack;
+  getSettings(): Record<string, any>;
+  pushData(channelData: Float32Array | Float32Array[] | ArrayBuffer | ArrayBufferView, options?: { channels?: number; numberOfChannels?: number; bitDepth?: 8 | 16 | 32 }): void;
+}
+
+export class MediaStream extends EventTarget {
+  readonly id: string;
+  readonly active: boolean;
+  constructor(tracks?: MediaStreamTrack[] | MediaStream);
+  getTracks(): MediaStreamTrack[];
+  getAudioTracks(): MediaStreamTrack[];
+  getVideoTracks(): MediaStreamTrack[];
+  addTrack(track: MediaStreamTrack): void;
+  removeTrack(track: MediaStreamTrack): void;
+}
+
 // Error types
 export class InvalidStateError extends Error { readonly name: 'InvalidStateError' }
 export class NotSupportedError extends Error { readonly name: 'NotSupportedError' }
diff --git a/index.js b/index.js
index 74a0bba..0252488 100644
--- a/index.js
+++ b/index.js
@@ -25,6 +25,7 @@ export { default as ScriptProcessorNode } from './src/ScriptProcessorNode.js'
 export { default as PannerNode } from './src/PannerNode/index.js'
 export { AudioWorkletNode, AudioWorkletProcessor } from './src/AudioWorklet.js'
 export { MediaStreamAudioSourceNode, MediaStreamAudioDestinationNode, MediaElementAudioSourceNode } from './src/MediaStreamAudioSourceNode.js'
+export { MediaStream, MediaStreamTrack } from './src/MediaStream.js'
 export { default as AudioListener } from './src/AudioListener.js'
 export { BLOCK_SIZE } from './src/constants.js'
 export { InvalidStateError, NotSupportedError, IndexSizeError, InvalidAccessError, EncodingError } from './src/errors.js'
diff --git a/polyfill.js b/polyfill.js
index e351c18..1fbeed0 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -1,8 +1,5 @@
 // Web Audio API globals for Node: `import 'web-audio-api/polyfill'`
-// Also exposes `navigator.mediaDevices.getUserMedia()` + MediaStream/Track so
-// browser mic code runs verbatim. Requires optional peer dep `audio-mic`.
 import * as waa from './index.js'
-import convert from 'pcm-convert'
 
 for (let [name, value] of Object.entries(waa))
   if (typeof value === 'function' && !(name in globalThis)) globalThis[name] = value
@@ -10,95 +7,5 @@ for (let [name, value] of Object.entries(waa))
 // Tone.js / standardized-audio-context checks `instanceof window.AudioParam`
 if (typeof window === 'undefined') globalThis.window = globalThis
 
-// --- MediaStream / MediaStreamTrack --------------------------------------
-// Minimal spec-shaped classes for `instanceof` + track.stop() in Node.
-
-let nextId = 0
-class MediaStreamTrack extends EventTarget {
-  kind; label; enabled = true; readyState = 'live'
-  id = 'track-' + (++nextId)
-  #settings
-  constructor(kind = 'audio', label = '', settings = {}) {
-    super(); this.kind = kind; this.label = label; this.#settings = settings
-  }
-  stop() {
-    if (this.readyState === 'ended') return
-    this.readyState = 'ended'
-    this.dispatchEvent(new Event('ended'))
-  }
-  clone() { return new MediaStreamTrack(this.kind, this.label, this.#settings) }
-  getSettings() { return { ...this.#settings } }
-}
-
-class MediaStream {
-  id = 'stream-' + Math.random().toString(36).slice(2)
-  #tracks
-  _buffers = []
-  constructor(tracks = []) { this.#tracks = [...(tracks instanceof MediaStream ? tracks.getTracks() : tracks)] }
-  get active() { return this.#tracks.some(t => t.readyState === 'live') }
-  getTracks() { return [...this.#tracks] }
-  getAudioTracks() { return this.#tracks.filter(t => t.kind === 'audio') }
-  getVideoTracks() { return this.#tracks.filter(t => t.kind === 'video') }
-  addTrack(t) { if (!this.#tracks.includes(t)) this.#tracks.push(t) }
-  removeTrack(t) { let i = this.#tracks.indexOf(t); if (i >= 0) this.#tracks.splice(i, 1) }
-}
-
-globalThis.MediaStreamTrack ??= MediaStreamTrack
-globalThis.MediaStream ??= MediaStream
-
-// --- navigator.mediaDevices.getUserMedia ---------------------------------
-
-let pick = v => v == null ? undefined : typeof v === 'number' ? v : (v.ideal ?? v.exact ?? v.min ?? v.max)
-let splitPlanar = (data, channels) => {
-  if (channels === 1) return data
-  let frames = data.length / channels
-  return Array.from({ length: channels }, (_, ch) => data.subarray(ch * frames, (ch + 1) * frames))
-}
-
-let toFloat32 = (chunk, opts) => {
-  if (chunk instanceof Float32Array || Array.isArray(chunk)) return chunk
-  if (![8, 16, 32].includes(opts.bitDepth))
-    throw new TypeError('getUserMedia PCM conversion supports 8, 16, or 32-bit integer samples')
-  let bytes = chunk instanceof ArrayBuffer
-    ? chunk
-    : chunk.buffer.slice(chunk.byteOffset, chunk.byteOffset + chunk.byteLength)
-  let data = convert(bytes, { dtype: `int${opts.bitDepth}`, channels: opts.channels, interleaved: true, endianness: 'le' },
-    { dtype: 'float32', channels: opts.channels, interleaved: false })
-  return splitPlanar(data, opts.channels)
-}
-
-async function getUserMedia(constraints = {}) {
-  if (!constraints.audio) throw Object.assign(new Error(
-    'getUserMedia: only { audio } is supported in Node'), { name: 'NotSupportedError' })
-
-  let mic
-  try { mic = (await import('audio-mic')).default }
-  catch { throw Object.assign(new Error(
-    "getUserMedia requires 'audio-mic' in Node. Install: npm install audio-mic"),
-    { name: 'NotFoundError' }) }
-
-  let c = constraints.audio === true ? {} : constraints.audio
-  let opts = { sampleRate: pick(c.sampleRate) ?? 44100, channels: pick(c.channelCount) ?? 1, bitDepth: pick(c.sampleSize) ?? 16 }
-  if (![8, 16, 32].includes(opts.bitDepth)) throw Object.assign(new Error(
-    'getUserMedia supports 8, 16, or 32-bit integer PCM samples in Node'),
-    { name: 'NotSupportedError' })
-  let read = mic(opts)
-  let track = new MediaStreamTrack('audio', 'Default audio input',
-    { sampleRate: opts.sampleRate, channelCount: opts.channels, sampleSize: opts.bitDepth })
-  let stream = new MediaStream([track])
-  let live = true
-  let pump = () => read((err, chunk) => {
-    if (!live || err || !chunk) return
-    stream._buffers.push(toFloat32(chunk, opts))
-    pump()
-  })
-  pump()
-
-  let origStop = track.stop.bind(track)
-  track.stop = () => { live = false; try { read(null); read.close?.() } catch {} origStop() }
-  return stream
-}
-
-globalThis.navigator ??= {}
-globalThis.navigator.mediaDevices ??= {}
-globalThis.navigator.mediaDevices.getUserMedia ??= getUserMedia
+globalThis.MediaStreamTrack ??= waa.MediaStreamTrack
+globalThis.MediaStream ??= waa.MediaStream
diff --git a/src/MediaStream.js b/src/MediaStream.js
new file mode 100644
index 0000000..5c6ad31
--- /dev/null
+++ b/src/MediaStream.js
@@ -0,0 +1,79 @@
+import convert from 'pcm-convert'
+
+let nextId = 0
+let splitPlanar = (data, channels) => {
+  if (channels === 1) return data
+  let frames = data.length / channels
+  let planes = []
+  for (let ch = 0; ch < channels; ch++) planes.push(data.subarray(ch * frames, (ch + 1) * frames))
+  return planes
+}
+
+let isFloatChunk = chunk =>
+  chunk instanceof Float32Array ||
+  (Array.isArray(chunk) && chunk.every(ch => ch instanceof Float32Array))
+
+let normalizeChunk = (chunk, channels, bitDepth) => {
+  if (isFloatChunk(chunk)) return chunk
+  if (![8, 16, 32].includes(bitDepth))
+    throw new TypeError('pushData PCM conversion supports 8, 16, or 32-bit integer samples')
+  if (!chunk?.buffer && !(chunk instanceof ArrayBuffer))
+    throw new TypeError('pushData expects Float32Array, Float32Array[], or interleaved PCM data')
+
+  let bytes = chunk instanceof ArrayBuffer
+    ? chunk
+    : chunk.buffer.slice(chunk.byteOffset, chunk.byteOffset + chunk.byteLength)
+  let data = convert(bytes, { dtype: `int${bitDepth}`, channels, interleaved: true, endianness: 'le' },
+    { dtype: 'float32', channels, interleaved: false })
+  return splitPlanar(data, channels)
+}
+
+export class MediaStreamTrack extends EventTarget {
+  id = 'track-' + (++nextId)
+  kind
+  label
+  enabled = true
+  readyState = 'live'
+  #settings
+  _buffers = []
+
+  constructor(kind = 'audio', label = '', settings = {}) {
+    super()
+    this.kind = kind
+    this.label = label
+    this.#settings = settings
+  }
+
+  stop() {
+    if (this.readyState === 'ended') return
+    this.readyState = 'ended'
+    this.dispatchEvent(new Event('ended'))
+  }
+
+  clone() { return new MediaStreamTrack(this.kind, this.label, this.#settings) }
+
+  getSettings() { return { ...this.#settings } }
+
+  pushData(chunk, options = {}) {
+    let channels = options.channels ?? options.numberOfChannels ?? this.#settings.channelCount ?? 1
+    let bitDepth = options.bitDepth ?? this.#settings.sampleSize ?? 16
+    this._buffers.push(normalizeChunk(chunk, channels, bitDepth))
+  }
+}
+
+export class MediaStream extends EventTarget {
+  id = 'stream-' + Math.random().toString(36).slice(2)
+  #tracks
+
+  constructor(tracks = []) {
+    super()
+    this.#tracks = [...(tracks instanceof MediaStream ? tracks.getTracks() : tracks)]
+  }
+
+  get active() { return this.#tracks.some(t => t.readyState === 'live') }
+  getTracks() { return [...this.#tracks] }
+  getAudioTracks() { return this.#tracks.filter(t => t.kind === 'audio') }
+  getVideoTracks() { return this.#tracks.filter(t => t.kind === 'video') }
+  addTrack(t) { if (!this.#tracks.includes(t)) this.#tracks.push(t) }
+  removeTrack(t) { let i = this.#tracks.indexOf(t); if (i >= 0) this.#tracks.splice(i, 1) }
+}
diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 62c48cd..ae0c8c6 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -1,44 +1,8 @@
 import AudioNode from './AudioNode.js'
 import AudioBuffer from 'audio-buffer'
-import convert from 'pcm-convert'
 import { BLOCK_SIZE } from './constants.js'
 import { DOMErr } from './errors.js'
-
-// Make a minimal MediaStreamTrack-shaped object (used by destination node below)
-let nextId = 0
-let makeTrack = (kind = 'audio', settings = {}) => ({
-  id: 'track-' + (++nextId), kind, enabled: true, readyState: 'live',
-  stop() { this.readyState = 'ended' },
-  clone() { return makeTrack(this.kind, settings) },
-  getSettings: () => ({ ...settings }),
-})
-
-let splitPlanar = (data, channels) => {
-  if (channels === 1) return data
-  let frames = data.length / channels
-  let planes = []
-  for (let ch = 0; ch < channels; ch++) planes.push(data.subarray(ch * frames, (ch + 1) * frames))
-  return planes
-}
-
-let isFloatChunk = chunk =>
-  chunk instanceof Float32Array ||
-  (Array.isArray(chunk) && chunk.every(ch => ch instanceof Float32Array))
-
-let normalizeChunk = (chunk, channels, bitDepth) => {
-  if (isFloatChunk(chunk)) return chunk
-  if (![8, 16, 32].includes(bitDepth))
-    throw new TypeError('pushData PCM conversion supports 8, 16, or 32-bit integer samples')
-  if (!chunk?.buffer && !(chunk instanceof ArrayBuffer))
-    throw new TypeError('pushData expects Float32Array, Float32Array[], or interleaved PCM data')
-
-  let bytes = chunk instanceof ArrayBuffer
-    ? chunk
-    : chunk.buffer.slice(chunk.byteOffset, chunk.byteOffset + chunk.byteLength)
-  let data = convert(bytes, { dtype: `int${bitDepth}`, channels, interleaved: true, endianness: 'le' },
-    { dtype: 'float32', channels, interleaved: false })
-  return splitPlanar(data, channels)
-}
+import { MediaStreamTrack } from './MediaStream.js'
 
 // Reads audio from a MediaStream-shaped source into the graph
 class MediaStreamAudioSourceNode extends AudioNode {
@@ -46,7 +10,6 @@ class MediaStreamAudioSourceNode extends AudioNode {
   #pending = null  // current chunk being drained
   #pos = 0
   #channels
-  #bitDepth
 
   get mediaStream() { return this.#stream }
 
@@ -56,32 +19,27 @@ class MediaStreamAudioSourceNode extends AudioNode {
     if (ms && (ms.getAudioTracks?.() ?? []).length === 0)
       throw DOMErr('MediaStream has no audio tracks', 'InvalidStateError')
 
-    let channels = options.numberOfChannels ?? 1
+    let track = ms?.getAudioTracks?.()[0]
+    let settings = track?.getSettings?.()
+    let channels = options.numberOfChannels ?? settings?.channelCount ?? 1
     super(context, 0, 1, channels, 'max', 'speakers')
     this.#stream = ms
     this.#channels = channels
-    this.#bitDepth = options.bitDepth ?? 16
     this._outBuf = new AudioBuffer(channels, BLOCK_SIZE, context.sampleRate)
     this._applyOpts(options)
   }
 
-  pushData(chunk, options = {}) {
-    ;(this.#stream ??= { _buffers: [] })._buffers ??= []
-    this.#stream._buffers.push(normalizeChunk(
-      chunk,
-      options.channels ?? options.numberOfChannels ?? this.#channels,
-      options.bitDepth ?? this.#bitDepth
-    ))
-  }
-
   _tick() {
     super._tick()
     let out = this._outBuf
     for (let ch = 0; ch < this.#channels; ch++) out.getChannelData(ch).fill(0)
 
+    let track = this.#stream?.getAudioTracks?.()[0]
+    let buffers = track?._buffers ?? this.#stream?._buffers
+
     let offset = 0
     while (offset < BLOCK_SIZE) {
-      if (!this.#pending) this.#pending = this.#stream?._buffers?.shift() ?? null
+      if (!this.#pending) this.#pending = buffers?.shift() ?? null
       if (!this.#pending) break
 
       let chunk = this.#pending
@@ -119,7 +77,7 @@ class MediaStreamAudioDestinationNode extends AudioNode {
     options = AudioNode._checkOpts(options)
     let channels = options.numberOfChannels ?? 2
     super(context, 1, 0, channels, 'explicit', 'speakers')
-    let track = makeTrack('audio', { channelCount: channels, sampleRate: context.sampleRate })
+    let track = new MediaStreamTrack('audio', '', { channelCount: channels, sampleRate: context.sampleRate })
     this.#stream = {
       _buffers: [],
       read() { return this._buffers.shift() || null },
diff --git a/test/MediaStreamNodes.test.js b/test/MediaStreamNodes.test.js
index cd525b4..99c50d5 100644
--- a/test/MediaStreamNodes.test.js
+++ b/test/MediaStreamNodes.test.js
@@ -5,17 +5,24 @@ import AudioNode from '../src/AudioNode.js'
 import AudioBuffer from 'audio-buffer'
 import { fill } from 'audio-buffer/util'
 import { MediaStreamAudioSourceNode, MediaStreamAudioDestinationNode } from '../src/MediaStreamAudioSourceNode.js'
+import { MediaStream, MediaStreamTrack } from '../src/MediaStream.js'
 import { BLOCK_SIZE } from '../src/constants.js'
 
 let mkCtx = () => new AudioContext()
 
+let mkStream = (opts) => {
+  let track = new MediaStreamTrack('audio', '', opts)
+  return new MediaStream([track])
+}
+
 test('MediaStreamAudioSourceNode > outputs pushed data', () => {
   let ctx = mkCtx()
-  let node = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
+  let stream = mkStream({ channelCount: 1 })
+  let node = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
 
   let data = new Float32Array(BLOCK_SIZE)
   data.fill(0.6)
-  node.pushData(data)
+  stream.getAudioTracks()[0].pushData(data)
 
   ctx._state = 'running'
   let buf = node._tick()
@@ -25,7 +32,8 @@ test('MediaStreamAudioSourceNode > outputs pushed data', () => {
 
 test('MediaStreamAudioSourceNode > outputs silence when no data', () => {
   let ctx = mkCtx()
-  let node = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
+  let stream = mkStream({ channelCount: 1 })
+  let node = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
 
   ctx._state = 'running'
   let buf = node._tick()
@@ -73,10 +81,11 @@ test('ctx.createMediaStreamSource > rejects non-MediaStream input', () => {
 
 test('MediaStreamAudioSourceNode > pushData converts Int16 PCM buffer', () => {
   let ctx = mkCtx()
-  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
+  let stream = mkStream({ channelCount: 1 })
+  let src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
   let pcm = Buffer.alloc(BLOCK_SIZE * 2)
   for (let i = 0; i < BLOCK_SIZE; i++) pcm.writeInt16LE(Math.round(0.5 * 32767), i * 2)
-  src.pushData(pcm, { channels: 1, bitDepth: 16 })
+  stream.getAudioTracks()[0].pushData(pcm, { channels: 1, bitDepth: 16 })
 
   ctx._state = 'running'
   let out = src._tick()
@@ -86,13 +95,14 @@ test('MediaStreamAudioSourceNode > pushData converts Int16 PCM buffer', () => {
 
 test('MediaStreamAudioSourceNode > pushData deinterleaves stereo PCM buffer', () => {
   let ctx = mkCtx()
-  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 2 })
+  let stream = mkStream({ channelCount: 2 })
+  let src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
   let pcm = Buffer.alloc(BLOCK_SIZE * 2 * 2)
   for (let i = 0; i < BLOCK_SIZE; i++) {
     pcm.writeInt16LE(Math.round(0.3 * 32767), (i * 2) * 2)
     pcm.writeInt16LE(Math.round(-0.4 * 32767), (i * 2 + 1) * 2)
   }
-  src.pushData(pcm, { channels: 2, bitDepth: 16 })
+  stream.getAudioTracks()[0].pushData(pcm, { channels: 2, bitDepth: 16 })
 
   ctx._state = 'running'
   let out = src._tick()
@@ -103,9 +113,10 @@ test('MediaStreamAudioSourceNode > pushData deinterleaves stereo PCM buffer', ()
 
 test('MediaStreamAudioSourceNode > queued chunks drain in order', () => {
   let ctx = mkCtx()
-  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
+  let stream = mkStream({ channelCount: 1 })
+  let src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
   let values = [0.1, 0.2, 0.3]
-  for (let v of values) src.pushData(new Float32Array(BLOCK_SIZE).fill(v))
+  for (let v of values) stream.getAudioTracks()[0].pushData(new Float32Array(BLOCK_SIZE).fill(v))
 
   ctx._state = 'running'
   for (let v of values) {
@@ -117,9 +128,10 @@ test('MediaStreamAudioSourceNode > queued chunks drain in order', () => {
 
 test('MediaStreamAudioSourceNode > short chunks fill the same quantum', () => {
   let ctx = mkCtx()
-  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
-  src.pushData(new Float32Array(32).fill(0.25))
-  src.pushData(new Float32Array(BLOCK_SIZE - 32).fill(-0.25))
+  let stream = mkStream({ channelCount: 1 })
+  let src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
+  stream.getAudioTracks()[0].pushData(new Float32Array(32).fill(0.25))
+  stream.getAudioTracks()[0].pushData(new Float32Array(BLOCK_SIZE - 32).fill(-0.25))
 
   ctx._state = 'running'
   let out = src._tick().getChannelData(0)
diff --git a/test/polyfill.test.js b/test/polyfill.test.js
index d87f2f7..3e801b6 100644
--- a/test/polyfill.test.js
+++ b/test/polyfill.test.js
@@ -6,7 +6,6 @@ test('polyfill > Web Audio + MediaStream globals', () => {
   ok(typeof globalThis.AudioContext === 'function')
   ok(typeof globalThis.MediaStream === 'function')
   ok(typeof globalThis.MediaStreamTrack === 'function')
-  ok(typeof navigator.mediaDevices.getUserMedia === 'function')
 })
 
 test('polyfill > MediaStreamTrack lifecycle', () => {
@@ -26,25 +25,6 @@ test('polyfill > MediaStream aggregates tracks', () => {
   ok(!s.active)
 })
 
-test('polyfill > getUserMedia rejects without audio constraint', async () => {
-  let err
-  try { await navigator.mediaDevices.getUserMedia({}) } catch (e) { err = e }
-  is(err?.name, 'NotSupportedError')
-})
-
-test('polyfill > getUserMedia({audio:true}) — real stream or NotFoundError', async () => {
-  let stream, err
-  try { stream = await navigator.mediaDevices.getUserMedia({ audio: true }) } catch (e) { err = e }
-  if (err) {
-    is(err.name, 'NotFoundError')
-    ok(/audio-mic/.test(err.message))
-  } else {
-    ok(stream instanceof MediaStream)
-    is(stream.getAudioTracks().length, 1)
-    stream.getTracks().forEach(t => t.stop())
-  }
-})
-
 test('polyfill > createMediaStreamSource accepts polyfill MediaStream', () => {
   let ctx = new AudioContext()
   let s = new MediaStream([new MediaStreamTrack('audio')])

From f6e8329fa807e583561377776bf9eef04893f72b Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Thu, 30 Apr 2026 08:22:00 -0400
Subject: [PATCH 02/24] Make safer CustomMediaStreamTrack

---
 README.md                     | 16 ++++++++++------
 examples/mic.js               |  4 ++--
 index.d.ts                    |  5 +++++
 index.js                      |  2 +-
 polyfill.js                   |  1 +
 src/MediaStream.js            | 26 ++++++++++++++++++++------
 test/MediaStreamNodes.test.js |  6 +++---
 test/polyfill.test.js         | 11 ++++++++++-
 8 files changed, 52 insertions(+), 19 deletions(-)

diff --git a/README.md b/README.md
index e8e5cb3..c546895 100644
--- a/README.md
+++ b/README.md
@@ -93,8 +93,8 @@ Beyond the spec, for Node.js. Not portable to browsers.
 
 - **`addModule(fn)`** — register a processor via callback instead of URL, no file needed
 - **`sinkId: stream`** — pipe PCM to any writable: `new AudioContext({ sinkId: process.stdout })` then `node synth.js | aplay -f cd`
-- **`numberOfChannels`, `bitDepth`** — control output format in the constructor
-- **`MediaStreamTrack`, `MediaStream`** — exposed from `web-audio-api`. `MediaStreamTrack` has a `pushData(chunk, options)` method to feed audio (e.g. from a microphone). See the [mic FAQ](#how-do-i-capture-audio-from-the-microphone).
+- **`numberOfChannels`, `bitDepth`** — control output format in the constructor.
+- **`CustomMediaStreamTrack`** — extends `MediaStreamTrack` with a public constructor and `pushData(chunk, options)` to feed audio data (e.g. from a microphone). Prior art: `CanvasCaptureMediaStreamTrack`. See the [mic FAQ](#how-do-i-capture-audio-from-the-microphone).
 
 ## FAQ
 
@@ -150,20 +150,24 @@ WAV, MP3, FLAC, OGG, AAC via [audio-decode](https://github.com/audiojs/audio-dec
 <dt id="how-do-i-capture-audio-from-the-microphone">How do I capture audio from the microphone?</dt>
 <dd>
 
-In Node, pair [`audio-mic`](https://github.com/audiojs/audio-mic) with `MediaStreamTrack.pushData()`:
+In Node, pair [`audio-mic`](https://github.com/audiojs/audio-mic) with `CustomMediaStreamTrack`:
 
 ```sh
 npm install audio-mic
 ```
 
 ```js
-import { AudioContext, MediaStreamAudioSourceNode, MediaStreamTrack, MediaStream } from 'web-audio-api'
+import { AudioContext, MediaStreamAudioSourceNode, CustomMediaStreamTrack, MediaStream } from 'web-audio-api'
 import mic from 'audio-mic'
 
 const ctx = new AudioContext()
 await ctx.resume()
 
-const track = new MediaStreamTrack('audio', 'mic', { channelCount: 1, sampleSize: 16, sampleRate: ctx.sampleRate })
+const track = new CustomMediaStreamTrack({
+  kind: 'audio',
+  label: 'mic',
+  settings: { channelCount: 1, sampleSize: 16, sampleRate: ctx.sampleRate }
+})
 const stream = new MediaStream([track])
 
 const src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
@@ -176,7 +180,7 @@ read((err, buf) => {
 })
 ```
 
-`track.pushData()` accepts `Float32Array`, `Float32Array[]`, or interleaved 8/16/32-bit integer PCM buffers. Integer PCM conversion uses `pcm-convert`.
+`track.pushData()` accepts `Float32Array`, `Float32Array[]`, or interleaved 8/16/32-bit integer PCM buffers. Integer PCM conversion uses `pcm-convert`. `CustomMediaStreamTrack` extends `MediaStreamTrack` — prior art: `CanvasCaptureMediaStreamTrack`.
 
 See [examples/mic.js](examples/mic.js) for a runnable demo with gain and VU meter. To record the graph to a buffer, use `OfflineAudioContext.startRendering()`. To capture live graph output as a stream, use `ctx.createMediaStreamDestination()`.
 </dd>
diff --git a/examples/mic.js b/examples/mic.js
index 26eb78e..26f4d00 100644
--- a/examples/mic.js
+++ b/examples/mic.js
@@ -5,7 +5,7 @@
 // Run: node examples/mic.js gain=0.8
 // Keys: space pause · + / - adjust gain · q quit
 
-import { AudioContext, MediaStreamAudioSourceNode, MediaStream, MediaStreamTrack } from 'web-audio-api'
+import { AudioContext, MediaStreamAudioSourceNode, MediaStream, CustomMediaStreamTrack } from 'web-audio-api'
 import mic from 'audio-mic'
 import { args, keys, status, clearLine, pausedTag } from './_util.js'
 
@@ -18,7 +18,7 @@ let bitDepth = parseInt($('bit', '16'))
 const ctx = new AudioContext({ sampleRate })
 await ctx.resume()
 
-const track = new MediaStreamTrack('audio', 'mic', { channelCount: channels, sampleSize: bitDepth, sampleRate })
+const track = new CustomMediaStreamTrack({ kind: 'audio', label: 'mic', settings: { channelCount: channels, sampleSize: bitDepth, sampleRate } })
 const stream = new MediaStream([track])
 
 const src = new MediaStreamAudioSourceNode(ctx, { mediaStream: stream })
diff --git a/index.d.ts b/index.d.ts
index 22ee1a4..d5987ef 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -278,7 +278,12 @@ export class MediaStreamTrack extends EventTarget {
   stop(): void;
   clone(): MediaStreamTrack;
   getSettings(): Record<string, any>;
+}
+
+export class CustomMediaStreamTrack extends MediaStreamTrack {
+  constructor(options?: { kind?: string; label?: string; settings?: Record<string, any> });
   pushData(channelData: Float32Array | Float32Array[] | ArrayBuffer | ArrayBufferView, options?: { channels?: number; numberOfChannels?: number; bitDepth?: 8 | 16 | 32 }): void;
+  clone(): CustomMediaStreamTrack;
 }
 
 export class MediaStream extends EventTarget {
diff --git a/index.js b/index.js
index 0252488..1bf0364 100644
--- a/index.js
+++ b/index.js
@@ -25,7 +25,7 @@ export { default as ScriptProcessorNode } from './src/ScriptProcessorNode.js'
 export { default as PannerNode } from './src/PannerNode/index.js'
 export { AudioWorkletNode, AudioWorkletProcessor } from './src/AudioWorklet.js'
 export { MediaStreamAudioSourceNode, MediaStreamAudioDestinationNode, MediaElementAudioSourceNode } from './src/MediaStreamAudioSourceNode.js'
-export { MediaStream, MediaStreamTrack } from './src/MediaStream.js'
+export { MediaStream, MediaStreamTrack, CustomMediaStreamTrack } from './src/MediaStream.js'
 export { default as AudioListener } from './src/AudioListener.js'
 export { BLOCK_SIZE } from './src/constants.js'
 export { InvalidStateError, NotSupportedError, IndexSizeError, InvalidAccessError, EncodingError } from './src/errors.js'
diff --git a/polyfill.js b/polyfill.js
index 1fbeed0..e29380b 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -9,3 +9,4 @@ if (typeof window === 'undefined') globalThis.window = globalThis
 
 globalThis.MediaStreamTrack ??= waa.MediaStreamTrack
 globalThis.MediaStream ??= waa.MediaStream
+globalThis.CustomMediaStreamTrack ??= waa.CustomMediaStreamTrack
diff --git a/src/MediaStream.js b/src/MediaStream.js
index 5c6ad31..abf67d5 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -28,14 +28,15 @@ let normalizeChunk = (chunk, channels, bitDepth) => {
   return splitPlanar(data, channels)
 }
 
+// Per W3C Media Capture spec, MediaStreamTrack has no public constructor.
+// We provide one as base class for subclassing (like CanvasCaptureMediaStreamTrack).
 export class MediaStreamTrack extends EventTarget {
   id = 'track-' + (++nextId)
-  kind
-  label
+  kind = 'audio'
+  label = ''
   enabled = true
   readyState = 'live'
-  #settings
-  _buffers = []
+  #settings = {}
 
   constructor(kind = 'audio', label = '', settings = {}) {
     super()
@@ -53,12 +54,25 @@ export class MediaStreamTrack extends EventTarget {
   clone() { return new MediaStreamTrack(this.kind, this.label, this.#settings) }
 
   getSettings() { return { ...this.#settings } }
+}
+
+// Node extension: custom track with public constructor and pushData().
+// Prior art: CanvasCaptureMediaStreamTrack extends MediaStreamTrack.
+export class CustomMediaStreamTrack extends MediaStreamTrack {
+  _buffers = []
+
+  constructor({ kind = 'audio', label = '', settings = {} } = {}) {
+    super(kind, label, settings)
+  }
 
   pushData(chunk, options = {}) {
-    let channels = options.channels ?? options.numberOfChannels ?? this.#settings.channelCount ?? 1
-    let bitDepth = options.bitDepth ?? this.#settings.sampleSize ?? 16
+    let settings = this.getSettings()
+    let channels = options.channels ?? options.numberOfChannels ?? settings.channelCount ?? 1
+    let bitDepth = options.bitDepth ?? settings.sampleSize ?? settings.bitDepth ?? 16
     this._buffers.push(normalizeChunk(chunk, channels, bitDepth))
   }
+
+  clone() { return new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() }) }
 }
 
 export class MediaStream extends EventTarget {
diff --git a/test/MediaStreamNodes.test.js b/test/MediaStreamNodes.test.js
index 99c50d5..bd911ea 100644
--- a/test/MediaStreamNodes.test.js
+++ b/test/MediaStreamNodes.test.js
@@ -5,13 +5,13 @@ import AudioNode from '../src/AudioNode.js'
 import AudioBuffer from 'audio-buffer'
 import { fill } from 'audio-buffer/util'
 import { MediaStreamAudioSourceNode, MediaStreamAudioDestinationNode } from '../src/MediaStreamAudioSourceNode.js'
-import { MediaStream, MediaStreamTrack } from '../src/MediaStream.js'
+import { MediaStream, CustomMediaStreamTrack } from '../src/MediaStream.js'
 import { BLOCK_SIZE } from '../src/constants.js'
 
 let mkCtx = () => new AudioContext()
 
-let mkStream = (opts) => {
-  let track = new MediaStreamTrack('audio', '', opts)
+let mkStream = (settings) => {
+  let track = new CustomMediaStreamTrack({ kind: 'audio', settings })
   return new MediaStream([track])
 }
 
diff --git a/test/polyfill.test.js b/test/polyfill.test.js
index 3e801b6..9daeb96 100644
--- a/test/polyfill.test.js
+++ b/test/polyfill.test.js
@@ -6,6 +6,7 @@ test('polyfill > Web Audio + MediaStream globals', () => {
   ok(typeof globalThis.AudioContext === 'function')
   ok(typeof globalThis.MediaStream === 'function')
   ok(typeof globalThis.MediaStreamTrack === 'function')
+  ok(typeof globalThis.CustomMediaStreamTrack === 'function')
 })
 
 test('polyfill > MediaStreamTrack lifecycle', () => {
@@ -15,6 +16,14 @@ test('polyfill > MediaStreamTrack lifecycle', () => {
   ok(t.clone() instanceof MediaStreamTrack)
 })
 
+test('polyfill > CustomMediaStreamTrack pushData', () => {
+  let t = new CustomMediaStreamTrack({ kind: 'audio', label: 'Mic', settings: { channelCount: 1 } })
+  is(t.kind, 'audio'); is(t.label, 'Mic'); is(t.readyState, 'live')
+  t.pushData(new Float32Array(128).fill(0.5))
+  is(t._buffers.length, 1)
+  ok(t.clone() instanceof CustomMediaStreamTrack)
+})
+
 test('polyfill > MediaStream aggregates tracks', () => {
   let a = new MediaStreamTrack('audio')
   let s = new MediaStream([a])
@@ -27,7 +36,7 @@ test('polyfill > MediaStream aggregates tracks', () => {
 
 test('polyfill > createMediaStreamSource accepts polyfill MediaStream', () => {
   let ctx = new AudioContext()
-  let s = new MediaStream([new MediaStreamTrack('audio')])
+  let s = new MediaStream([new CustomMediaStreamTrack({ kind: 'audio' })])
   let node = ctx.createMediaStreamSource(s)
   is(node.mediaStream, s)
 })

From ea2f4b1e3b8103d2f8269a972892e9b23f8d3895 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Fri, 1 May 2026 20:09:20 -0400
Subject: [PATCH 03/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 polyfill.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/polyfill.js b/polyfill.js
index e29380b..d51862f 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -10,3 +10,10 @@ if (typeof window === 'undefined') globalThis.window = globalThis
 globalThis.MediaStreamTrack ??= waa.MediaStreamTrack
 globalThis.MediaStream ??= waa.MediaStream
 globalThis.CustomMediaStreamTrack ??= waa.CustomMediaStreamTrack
+
+if (typeof waa.getUserMedia === 'function') {
+  globalThis.navigator ??= {}
+  globalThis.navigator.mediaDevices ??= {}
+  globalThis.navigator.mediaDevices.getUserMedia ??= waa.getUserMedia.bind(waa)
+  globalThis.navigator.getUserMedia ??= globalThis.navigator.mediaDevices.getUserMedia
+}

From 7e9bd01441f62a865cc8b3accd8c84ecf47d2633 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 00:11:27 +0000
Subject: [PATCH 04/24] fix: CustomMediaStreamTrack.clone() shares _buffers
 with original

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/65b9b190-f4f3-4010-b138-002f2c928f29

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 package-lock.json  | 9 +++++++++
 src/MediaStream.js | 6 +++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/package-lock.json b/package-lock.json
index 5d37f34..09aadc3 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -27,6 +27,14 @@
       },
       "engines": {
         "node": ">=18"
+      },
+      "peerDependencies": {
+        "audio-mic": "*"
+      },
+      "peerDependenciesMeta": {
+        "audio-mic": {
+          "optional": true
+        }
       }
     },
     "node_modules/@audio/aac-decode": {
@@ -262,6 +270,7 @@
     },
     "node_modules/audio-speaker": {
       "version": "2.0.5",
+      "hasInstallScript": true,
       "license": "MIT",
       "engines": {
         "node": ">=18"
diff --git a/src/MediaStream.js b/src/MediaStream.js
index abf67d5..10cf987 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -72,7 +72,11 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
     this._buffers.push(normalizeChunk(chunk, channels, bitDepth))
   }
 
-  clone() { return new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() }) }
+  clone() {
+    let clone = new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() })
+    clone._buffers = this._buffers
+    return clone
+  }
 }
 
 export class MediaStream extends EventTarget {

From d0cd67a1bfe9a4d5c77bc570d3d6b9e3da837e71 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 00:13:59 +0000
Subject: [PATCH 05/24] fix: enforce track lifecycle in pushData and _tick

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/7235af34-e944-4ffd-a5d3-799530153992

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 src/MediaStream.js                |  1 +
 src/MediaStreamAudioSourceNode.js | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 10cf987..9ce32d9 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -66,6 +66,7 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
   }
 
   pushData(chunk, options = {}) {
+    if (this.readyState === 'ended') return
     let settings = this.getSettings()
     let channels = options.channels ?? options.numberOfChannels ?? settings.channelCount ?? 1
     let bitDepth = options.bitDepth ?? settings.sampleSize ?? settings.bitDepth ?? 16
diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index ae0c8c6..48fe0c5 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -35,6 +35,17 @@ class MediaStreamAudioSourceNode extends AudioNode {
     for (let ch = 0; ch < this.#channels; ch++) out.getChannelData(ch).fill(0)
 
     let track = this.#stream?.getAudioTracks?.()[0]
+
+    // go silent and clear state if track has ended
+    if (track?.readyState === 'ended') {
+      this.#pending = null
+      this.#pos = 0
+      return out
+    }
+
+    // go silent without draining if track is disabled (resumes on re-enable)
+    if (track && !track.enabled) return out
+
     let buffers = track?._buffers ?? this.#stream?._buffers
 
     let offset = 0

From a804a69cb24fadb158da59627ccb90c561967526 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Fri, 1 May 2026 21:08:31 -0400
Subject: [PATCH 06/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 9ce32d9..2e660ee 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -32,22 +32,28 @@ let normalizeChunk = (chunk, channels, bitDepth) => {
 // We provide one as base class for subclassing (like CanvasCaptureMediaStreamTrack).
 export class MediaStreamTrack extends EventTarget {
   id = 'track-' + (++nextId)
-  kind = 'audio'
-  label = ''
+  #kind = 'audio'
+  #label = ''
   enabled = true
-  readyState = 'live'
+  #readyState = 'live'
   #settings = {}
 
   constructor(kind = 'audio', label = '', settings = {}) {
     super()
-    this.kind = kind
-    this.label = label
+    this.#kind = kind
+    this.#label = label
     this.#settings = settings
   }
 
+  get kind() { return this.#kind }
+
+  get label() { return this.#label }
+
+  get readyState() { return this.#readyState }
+
   stop() {
-    if (this.readyState === 'ended') return
-    this.readyState = 'ended'
+    if (this.#readyState === 'ended') return
+    this.#readyState = 'ended'
     this.dispatchEvent(new Event('ended'))
   }
 

From 981e2fcd607f0e74eb3684facc4aac4ca166533e Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Fri, 1 May 2026 21:08:39 -0400
Subject: [PATCH 07/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 2e660ee..4c909c2 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -95,10 +95,27 @@ export class MediaStream extends EventTarget {
     this.#tracks = [...(tracks instanceof MediaStream ? tracks.getTracks() : tracks)]
   }
 
+  #dispatchTrackEvent(type, track) {
+    let event = new Event(type)
+    Object.defineProperty(event, 'track', { value: track, enumerable: true })
+    this.dispatchEvent(event)
+  }
+
   get active() { return this.#tracks.some(t => t.readyState === 'live') }
   getTracks() { return [...this.#tracks] }
   getAudioTracks() { return this.#tracks.filter(t => t.kind === 'audio') }
   getVideoTracks() { return this.#tracks.filter(t => t.kind === 'video') }
-  addTrack(t) { if (!this.#tracks.includes(t)) this.#tracks.push(t) }
-  removeTrack(t) { let i = this.#tracks.indexOf(t); if (i >= 0) this.#tracks.splice(i, 1) }
+  addTrack(t) {
+    if (!this.#tracks.includes(t)) {
+      this.#tracks.push(t)
+      this.#dispatchTrackEvent('addtrack', t)
+    }
+  }
+  removeTrack(t) {
+    let i = this.#tracks.indexOf(t)
+    if (i >= 0) {
+      this.#tracks.splice(i, 1)
+      this.#dispatchTrackEvent('removetrack', t)
+    }
+  }
 }

From 377a61b5c2d09235b10e501e87140e820c3526f6 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Fri, 1 May 2026 21:08:48 -0400
Subject: [PATCH 08/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 polyfill.js | 35 ++++++++++++++++++++++++++++++-----
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/polyfill.js b/polyfill.js
index d51862f..c59f232 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -11,9 +11,34 @@ globalThis.MediaStreamTrack ??= waa.MediaStreamTrack
 globalThis.MediaStream ??= waa.MediaStream
 globalThis.CustomMediaStreamTrack ??= waa.CustomMediaStreamTrack
 
-if (typeof waa.getUserMedia === 'function') {
-  globalThis.navigator ??= {}
-  globalThis.navigator.mediaDevices ??= {}
-  globalThis.navigator.mediaDevices.getUserMedia ??= waa.getUserMedia.bind(waa)
-  globalThis.navigator.getUserMedia ??= globalThis.navigator.mediaDevices.getUserMedia
+globalThis.navigator ??= {}
+globalThis.navigator.mediaDevices ??= {}
+
+const legacyGetUserMedia = typeof globalThis.navigator.getUserMedia === 'function'
+  ? globalThis.navigator.getUserMedia.bind(globalThis.navigator)
+  : undefined
+
+const installedGetUserMedia =
+  typeof waa.getUserMedia === 'function'
+    ? waa.getUserMedia.bind(waa)
+    : typeof legacyGetUserMedia === 'function'
+      ? (constraints) =>
+          new Promise((resolve, reject) => {
+            legacyGetUserMedia(constraints, resolve, reject)
+          })
+      : () =>
+          Promise.reject(
+            new TypeError('navigator.mediaDevices.getUserMedia is not implemented')
+          )
+
+globalThis.navigator.mediaDevices.getUserMedia ??= installedGetUserMedia
+globalThis.navigator.getUserMedia ??= function (constraints, successCallback, errorCallback) {
+  globalThis.navigator.mediaDevices.getUserMedia(constraints).then(
+    (stream) => {
+      if (typeof successCallback === 'function') successCallback(stream)
+    },
+    (error) => {
+      if (typeof errorCallback === 'function') errorCallback(error)
+    }
+  )
 }

From e346bcbc235b8f83c25af2f8926bd3cd5168e1ad Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 01:11:12 +0000
Subject: [PATCH 09/24] fix: use CustomMediaStreamTrack in destination node so
 clone() shares buffers

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/27f3cc8d-37f9-4feb-865a-8f33d5b75a8a

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 src/MediaStreamAudioSourceNode.js | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 48fe0c5..7959139 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -2,7 +2,7 @@ import AudioNode from './AudioNode.js'
 import AudioBuffer from 'audio-buffer'
 import { BLOCK_SIZE } from './constants.js'
 import { DOMErr } from './errors.js'
-import { MediaStreamTrack } from './MediaStream.js'
+import { CustomMediaStreamTrack } from './MediaStream.js'
 
 // Reads audio from a MediaStream-shaped source into the graph
 class MediaStreamAudioSourceNode extends AudioNode {
@@ -82,17 +82,19 @@ class MediaStreamAudioSourceNode extends AudioNode {
 // Captures graph output into a MediaStream for external consumers.
 class MediaStreamAudioDestinationNode extends AudioNode {
   #stream
+  #track
   get stream() { return this.#stream }
 
   constructor(context, options) {
     options = AudioNode._checkOpts(options)
     let channels = options.numberOfChannels ?? 2
     super(context, 1, 0, channels, 'explicit', 'speakers')
-    let track = new MediaStreamTrack('audio', '', { channelCount: channels, sampleRate: context.sampleRate })
+    let track = new CustomMediaStreamTrack({ kind: 'audio', settings: { channelCount: channels, sampleRate: context.sampleRate } })
+    this.#track = track
     this.#stream = {
-      _buffers: [],
-      read() { return this._buffers.shift() || null },
-      get readable() { return this._buffers.length > 0 },
+      get _buffers() { return track._buffers },
+      read() { return track._buffers.shift() || null },
+      get readable() { return track._buffers.length > 0 },
       getTracks: () => [track],
       getAudioTracks: () => [track],
       getVideoTracks: () => [],
@@ -106,7 +108,7 @@ class MediaStreamAudioDestinationNode extends AudioNode {
     let inBuf = this._inputs[0]._tick()
     let chunk = []
     for (let ch = 0; ch < inBuf.numberOfChannels; ch++) chunk.push(new Float32Array(inBuf.getChannelData(ch)))
-    this.#stream._buffers.push(chunk)
+    this.#track._buffers.push(chunk)
     return inBuf
   }
 }

From 94d8f19b5a765d61285649a4acb0af84451c8a75 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 01:15:46 +0000
Subject: [PATCH 10/24] fix: cache track in source node; fan-out clone pattern
 with auto-cleanup

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/9e18cfad-5d7c-4809-b293-e4c1f3de4c01

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 src/MediaStream.js                | 13 +++++++++++--
 src/MediaStreamAudioSourceNode.js |  6 ++++--
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 4c909c2..807e03d 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -66,22 +66,31 @@ export class MediaStreamTrack extends EventTarget {
 // Prior art: CanvasCaptureMediaStreamTrack extends MediaStreamTrack.
 export class CustomMediaStreamTrack extends MediaStreamTrack {
   _buffers = []
+  #clones = new Set()
 
   constructor({ kind = 'audio', label = '', settings = {} } = {}) {
     super(kind, label, settings)
   }
 
+  // Internal: fan out an already-normalised chunk to this track and all live clones.
+  _pushNormalized(chunk) {
+    this._buffers.push(chunk)
+    for (let clone of this.#clones) clone._pushNormalized(chunk)
+  }
+
   pushData(chunk, options = {}) {
     if (this.readyState === 'ended') return
     let settings = this.getSettings()
     let channels = options.channels ?? options.numberOfChannels ?? settings.channelCount ?? 1
     let bitDepth = options.bitDepth ?? settings.sampleSize ?? settings.bitDepth ?? 16
-    this._buffers.push(normalizeChunk(chunk, channels, bitDepth))
+    this._pushNormalized(normalizeChunk(chunk, channels, bitDepth))
   }
 
   clone() {
     let clone = new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() })
-    clone._buffers = this._buffers
+    this.#clones.add(clone)
+    // Remove from fan-out set when the clone ends to avoid memory leaks.
+    clone.addEventListener('ended', () => this.#clones.delete(clone), { once: true })
     return clone
   }
 }
diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 7959139..6cdaf5e 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -7,6 +7,7 @@ import { CustomMediaStreamTrack } from './MediaStream.js'
 // Reads audio from a MediaStream-shaped source into the graph
 class MediaStreamAudioSourceNode extends AudioNode {
   #stream
+  #track   // cached first audio track — avoids per-quantum getAudioTracks() allocation
   #pending = null  // current chunk being drained
   #pos = 0
   #channels
@@ -24,6 +25,7 @@ class MediaStreamAudioSourceNode extends AudioNode {
     let channels = options.numberOfChannels ?? settings?.channelCount ?? 1
     super(context, 0, 1, channels, 'max', 'speakers')
     this.#stream = ms
+    this.#track = track ?? null
     this.#channels = channels
     this._outBuf = new AudioBuffer(channels, BLOCK_SIZE, context.sampleRate)
     this._applyOpts(options)
@@ -34,7 +36,7 @@ class MediaStreamAudioSourceNode extends AudioNode {
     let out = this._outBuf
     for (let ch = 0; ch < this.#channels; ch++) out.getChannelData(ch).fill(0)
 
-    let track = this.#stream?.getAudioTracks?.()[0]
+    let track = this.#track
 
     // go silent and clear state if track has ended
     if (track?.readyState === 'ended') {
@@ -108,7 +110,7 @@ class MediaStreamAudioDestinationNode extends AudioNode {
     let inBuf = this._inputs[0]._tick()
     let chunk = []
     for (let ch = 0; ch < inBuf.numberOfChannels; ch++) chunk.push(new Float32Array(inBuf.getChannelData(ch)))
-    this.#track._buffers.push(chunk)
+    this.#track._pushNormalized(chunk)
     return inBuf
   }
 }

From 526c715cb336f3b518f007394db64e2260f89c7d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 03:54:12 +0000
Subject: [PATCH 11/24] fix: destination track lifecycle, WeakRef clones,
 pushData() compat shim, new tests

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/d596fb48-5208-4d87-870a-2037c2776bf0

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 index.d.ts                        |  1 +
 src/MediaStream.js                | 21 ++++++++---
 src/MediaStreamAudioSourceNode.js | 24 ++++++++----
 test/MediaStreamNodes.test.js     | 61 +++++++++++++++++++++++++++++++
 test/polyfill.test.js             |  5 +++
 5 files changed, 99 insertions(+), 13 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d5987ef..079636b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -259,6 +259,7 @@ export class AudioWorkletProcessor {
 
 export class MediaStreamAudioSourceNode extends AudioNode {
   readonly mediaStream: any;
+  pushData(channelData: Float32Array | Float32Array[] | ArrayBuffer | ArrayBufferView, options?: { channels?: number; numberOfChannels?: number; bitDepth?: 8 | 16 | 32 }): void;
 }
 
 export class MediaStreamAudioDestinationNode extends AudioNode {
diff --git a/src/MediaStream.js b/src/MediaStream.js
index 807e03d..02dcd53 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -66,7 +66,9 @@ export class MediaStreamTrack extends EventTarget {
 // Prior art: CanvasCaptureMediaStreamTrack extends MediaStreamTrack.
 export class CustomMediaStreamTrack extends MediaStreamTrack {
   _buffers = []
-  #clones = new Set()
+  // WeakRef-based fan-out: clones can be GC'd when no external reference is held.
+  #clones = new Set()  // Set<WeakRef<CustomMediaStreamTrack>>
+  #registry = new FinalizationRegistry(ref => this.#clones.delete(ref))
 
   constructor({ kind = 'audio', label = '', settings = {} } = {}) {
     super(kind, label, settings)
@@ -75,7 +77,11 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
   // Internal: fan out an already-normalised chunk to this track and all live clones.
   _pushNormalized(chunk) {
     this._buffers.push(chunk)
-    for (let clone of this.#clones) clone._pushNormalized(chunk)
+    for (let ref of this.#clones) {
+      let clone = ref.deref()
+      if (clone) clone._pushNormalized(chunk)
+      else this.#clones.delete(ref)
+    }
   }
 
   pushData(chunk, options = {}) {
@@ -88,9 +94,14 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
 
   clone() {
     let clone = new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() })
-    this.#clones.add(clone)
-    // Remove from fan-out set when the clone ends to avoid memory leaks.
-    clone.addEventListener('ended', () => this.#clones.delete(clone), { once: true })
+    let ref = new WeakRef(clone)
+    this.#clones.add(ref)
+    this.#registry.register(clone, ref, clone)
+    // Also eagerly clean up when the clone is explicitly stopped.
+    clone.addEventListener('ended', () => {
+      this.#registry.unregister(clone)
+      this.#clones.delete(ref)
+    }, { once: true })
     return clone
   }
 }
diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 6cdaf5e..0dcfb3d 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -20,17 +20,23 @@ class MediaStreamAudioSourceNode extends AudioNode {
     if (ms && (ms.getAudioTracks?.() ?? []).length === 0)
       throw DOMErr('MediaStream has no audio tracks', 'InvalidStateError')
 
-    let track = ms?.getAudioTracks?.()[0]
+    let track = ms?.getAudioTracks?.()[0] ?? null
     let settings = track?.getSettings?.()
     let channels = options.numberOfChannels ?? settings?.channelCount ?? 1
     super(context, 0, 1, channels, 'max', 'speakers')
     this.#stream = ms
-    this.#track = track ?? null
+    // When no MediaStream is given, create an internal track so pushData() still works.
+    this.#track = track ?? new CustomMediaStreamTrack({ settings: { channelCount: channels } })
     this.#channels = channels
     this._outBuf = new AudioBuffer(channels, BLOCK_SIZE, context.sampleRate)
     this._applyOpts(options)
   }
 
+  // Backward-compatible entry point: delegates to the track's pushData().
+  pushData(chunk, options = {}) {
+    this.#track.pushData(chunk, options)
+  }
+
   _tick() {
     super._tick()
     let out = this._outBuf
@@ -39,16 +45,16 @@ class MediaStreamAudioSourceNode extends AudioNode {
     let track = this.#track
 
     // go silent and clear state if track has ended
-    if (track?.readyState === 'ended') {
+    if (track.readyState === 'ended') {
       this.#pending = null
       this.#pos = 0
       return out
     }
 
     // go silent without draining if track is disabled (resumes on re-enable)
-    if (track && !track.enabled) return out
+    if (!track.enabled) return out
 
-    let buffers = track?._buffers ?? this.#stream?._buffers
+    let buffers = track._buffers ?? this.#stream?._buffers
 
     let offset = 0
     while (offset < BLOCK_SIZE) {
@@ -108,9 +114,11 @@ class MediaStreamAudioDestinationNode extends AudioNode {
   _tick() {
     super._tick()
     let inBuf = this._inputs[0]._tick()
-    let chunk = []
-    for (let ch = 0; ch < inBuf.numberOfChannels; ch++) chunk.push(new Float32Array(inBuf.getChannelData(ch)))
-    this.#track._pushNormalized(chunk)
+    if (this.#track.readyState !== 'ended') {
+      let chunk = []
+      for (let ch = 0; ch < inBuf.numberOfChannels; ch++) chunk.push(new Float32Array(inBuf.getChannelData(ch)))
+      this.#track._pushNormalized(chunk)
+    }
     return inBuf
   }
 }
diff --git a/test/MediaStreamNodes.test.js b/test/MediaStreamNodes.test.js
index bd911ea..1714955 100644
--- a/test/MediaStreamNodes.test.js
+++ b/test/MediaStreamNodes.test.js
@@ -140,3 +140,64 @@ test('MediaStreamAudioSourceNode > short chunks fill the same quantum', () => {
   almost(out[32], -0.25, 1e-6, 'second chunk continues in same quantum')
   almost(out[BLOCK_SIZE - 1], -0.25, 1e-6, 'second chunk fills quantum')
 })
+
+test('MediaStreamAudioSourceNode > pushData() compat: works without MediaStream', () => {
+  let ctx = mkCtx()
+  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1 })
+  src.pushData(new Float32Array(BLOCK_SIZE).fill(0.5))
+
+  ctx._state = 'running'
+  let out = src._tick()
+  almost(out.getChannelData(0)[0], 0.5, 1e-6, 'legacy pushData() still works')
+})
+
+test('MediaStreamAudioDestinationNode > stops capturing after track.stop()', () => {
+  let ctx = mkCtx()
+  let dest = new MediaStreamAudioDestinationNode(ctx, { numberOfChannels: 1 })
+  let src = new AudioNode(ctx, 0, 1)
+  src.connect(dest)
+  src._tick = () => { let b = new AudioBuffer(1, BLOCK_SIZE, 44100); b.getChannelData(0).fill(0.7); return b }
+
+  ctx._state = 'running'
+  dest._tick()
+  ok(dest.stream.readable, 'has data before stop')
+
+  // drain the queue then stop the track
+  while (dest.stream.readable) dest.stream.read()
+  dest.stream.getAudioTracks()[0].stop()
+  dest._tick()
+  ok(!dest.stream.readable, 'no new data after track.stop()')
+})
+
+test('CustomMediaStreamTrack > clone fan-out: clone receives future chunks', () => {
+  let track = new CustomMediaStreamTrack({})
+  let clone = track.clone()
+
+  track.pushData(new Float32Array(BLOCK_SIZE).fill(0.3))
+  is(clone._buffers.length, 1, 'clone receives pushed chunk')
+  almost(clone._buffers[0][0], 0.3, 1e-6, 'clone chunk has correct data')
+})
+
+test('CustomMediaStreamTrack > clone fan-out: stop() unsubscribes clone', () => {
+  let track = new CustomMediaStreamTrack({})
+  let clone = track.clone()
+  clone.stop()
+
+  track.pushData(new Float32Array(BLOCK_SIZE).fill(0.3))
+  is(clone._buffers.length, 0, 'stopped clone no longer receives data')
+})
+
+test('MediaStream > addTrack / removeTrack fire events with event.track', () => {
+  let stream = new MediaStream()
+  let track = new CustomMediaStreamTrack({ kind: 'audio' })
+
+  let added = null, removed = null
+  stream.addEventListener('addtrack', e => { added = e.track })
+  stream.addEventListener('removetrack', e => { removed = e.track })
+
+  stream.addTrack(track)
+  ok(added === track, 'addtrack event fired with correct track')
+
+  stream.removeTrack(track)
+  ok(removed === track, 'removetrack event fired with correct track')
+})
diff --git a/test/polyfill.test.js b/test/polyfill.test.js
index 9daeb96..d1a6482 100644
--- a/test/polyfill.test.js
+++ b/test/polyfill.test.js
@@ -40,3 +40,8 @@ test('polyfill > createMediaStreamSource accepts polyfill MediaStream', () => {
   let node = ctx.createMediaStreamSource(s)
   is(node.mediaStream, s)
 })
+
+test('polyfill > navigator.mediaDevices.getUserMedia is a function', () => {
+  ok(typeof globalThis.navigator.mediaDevices.getUserMedia === 'function',
+    'getUserMedia installed on mediaDevices')
+})

From d86de1ffbe1f8eaac2c0a8d78c59e8982c9f08a8 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Fri, 1 May 2026 23:56:07 -0400
Subject: [PATCH 12/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStreamAudioSourceNode.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 0dcfb3d..e54f0c3 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -110,7 +110,7 @@ class MediaStreamAudioDestinationNode extends AudioNode {
     this._applyOpts(options)
     context._tailNodes?.add(this)
   }
-
+    if (this.#track?.readyState !== 'ended') this.#track._pushNormalized(chunk)
   _tick() {
     super._tick()
     let inBuf = this._inputs[0]._tick()

From 38acf7af679697bf6fe5d3e2b94cb41dabecbb5c Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 00:04:33 -0400
Subject: [PATCH 13/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStreamAudioSourceNode.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index e54f0c3..04120ce 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -23,10 +23,16 @@ class MediaStreamAudioSourceNode extends AudioNode {
     let track = ms?.getAudioTracks?.()[0] ?? null
     let settings = track?.getSettings?.()
     let channels = options.numberOfChannels ?? settings?.channelCount ?? 1
+    let bitDepth = options.bitDepth ?? settings?.bitDepth
     super(context, 0, 1, channels, 'max', 'speakers')
     this.#stream = ms
     // When no MediaStream is given, create an internal track so pushData() still works.
-    this.#track = track ?? new CustomMediaStreamTrack({ settings: { channelCount: channels } })
+    this.#track = track ?? new CustomMediaStreamTrack({
+      settings: {
+        channelCount: channels,
+        ...(bitDepth == null ? {} : { bitDepth })
+      }
+    })
     this.#channels = channels
     this._outBuf = new AudioBuffer(channels, BLOCK_SIZE, context.sampleRate)
     this._applyOpts(options)

From 4e85c1cb89ecb6878a16dd3d47abc5d3ef9efe0c Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 00:04:44 -0400
Subject: [PATCH 14/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 02dcd53..a7f8b71 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -97,11 +97,22 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
     let ref = new WeakRef(clone)
     this.#clones.add(ref)
     this.#registry.register(clone, ref, clone)
-    // Also eagerly clean up when the clone is explicitly stopped.
+
+    let stopCloneWhenSourceEnds = () => {
+      if (clone.readyState !== 'ended') clone.stop()
+    }
+
+    // Clones are fed through this source track, so they must end when the source ends.
+    this.addEventListener('ended', stopCloneWhenSourceEnds, { once: true })
+
+    // Also eagerly clean up when the clone is explicitly stopped or is ended via the source.
     clone.addEventListener('ended', () => {
       this.#registry.unregister(clone)
       this.#clones.delete(ref)
     }, { once: true })
+
+    if (this.readyState === 'ended') stopCloneWhenSourceEnds()
+
     return clone
   }
 }

From a43c4d7c086f78e70af3a5a5570075e769484cc2 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 00:04:53 -0400
Subject: [PATCH 15/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 test/polyfill.test.js | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/test/polyfill.test.js b/test/polyfill.test.js
index d1a6482..db1423e 100644
--- a/test/polyfill.test.js
+++ b/test/polyfill.test.js
@@ -41,7 +41,23 @@ test('polyfill > createMediaStreamSource accepts polyfill MediaStream', () => {
   is(node.mediaStream, s)
 })
 
-test('polyfill > navigator.mediaDevices.getUserMedia is a function', () => {
+test('polyfill > navigator.mediaDevices.getUserMedia acquires or meaningfully rejects microphone streams', async () => {
   ok(typeof globalThis.navigator.mediaDevices.getUserMedia === 'function',
     'getUserMedia installed on mediaDevices')
+
+  let result = globalThis.navigator.mediaDevices.getUserMedia({ audio: true })
+  ok(result && typeof result.then === 'function',
+    'getUserMedia returns a promise')
+
+  try {
+    let stream = await result
+    ok(stream instanceof MediaStream, 'resolved value is a MediaStream')
+    ok(stream.getAudioTracks().length > 0,
+      'resolved stream exposes at least one audio track')
+  } catch (err) {
+    ok(err instanceof Error || (err && typeof err === 'object'),
+      'rejection is Error-like')
+    ok(!!(err && typeof err.message === 'string' && err.message.length > 0),
+      'rejection includes a non-empty message')
+  }
 })

From a7e1879f8d0b73c4b8d2e68f3292448bb49291fb Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 00:05:01 -0400
Subject: [PATCH 16/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 test/MediaStreamNodes.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/MediaStreamNodes.test.js b/test/MediaStreamNodes.test.js
index 1714955..3eb44db 100644
--- a/test/MediaStreamNodes.test.js
+++ b/test/MediaStreamNodes.test.js
@@ -151,6 +151,22 @@ test('MediaStreamAudioSourceNode > pushData() compat: works without MediaStream'
   almost(out.getChannelData(0)[0], 0.5, 1e-6, 'legacy pushData() still works')
 })
 
+test('MediaStreamAudioSourceNode > pushData() compat: uses constructor bitDepth for raw PCM when call options are omitted', () => {
+  let ctx = mkCtx()
+  let src = new MediaStreamAudioSourceNode(ctx, { numberOfChannels: 1, bitDepth: 16 })
+  let samples = new Int16Array(BLOCK_SIZE)
+  samples[0] = 32767
+  samples[1] = -32768
+  samples[2] = 16384
+  src.pushData(samples)
+
+  ctx._state = 'running'
+  let out = src._tick().getChannelData(0)
+  almost(out[0], 32767 / 32768, 1e-6, 'decodes positive 16-bit PCM using constructor bitDepth')
+  almost(out[1], -1, 1e-6, 'decodes negative 16-bit PCM using constructor bitDepth')
+  almost(out[2], 0.5, 1e-6, 'decodes mid-scale 16-bit PCM using constructor bitDepth')
+})
+
 test('MediaStreamAudioDestinationNode > stops capturing after track.stop()', () => {
   let ctx = mkCtx()
   let dest = new MediaStreamAudioDestinationNode(ctx, { numberOfChannels: 1 })

From 12cd5e026d7a8801d68a7aacd5cf93f12673b8da Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 04:10:39 +0000
Subject: [PATCH 17/24] fix: restore audio-mic-backed getUserMedia in polyfill;
 fix stray fragment in dest node

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/5c1f80bb-b76b-4ff2-9b7f-c8ca82dc86c5

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 polyfill.js                       | 73 ++++++++++++++++++++++---------
 src/MediaStreamAudioSourceNode.js |  2 +-
 test/MediaStreamNodes.test.js     |  4 +-
 3 files changed, 56 insertions(+), 23 deletions(-)

diff --git a/polyfill.js b/polyfill.js
index c59f232..e89828e 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -1,4 +1,6 @@
 // Web Audio API globals for Node: `import 'web-audio-api/polyfill'`
+// Also exposes `navigator.mediaDevices.getUserMedia()` backed by the optional
+// peer dep `audio-mic` so browser mic code runs verbatim.
 import * as waa from './index.js'
 
 for (let [name, value] of Object.entries(waa))
@@ -14,31 +16,62 @@ globalThis.CustomMediaStreamTrack ??= waa.CustomMediaStreamTrack
 globalThis.navigator ??= {}
 globalThis.navigator.mediaDevices ??= {}
 
+// --- navigator.mediaDevices.getUserMedia ---------------------------------
+// Backed by the optional 'audio-mic' peer dep.  Install: npm install audio-mic
+
+let pick = v => v == null ? undefined : typeof v === 'number' ? v : (v.ideal ?? v.exact ?? v.min ?? v.max)
+
+async function getUserMedia(constraints = {}) {
+  if (!constraints.audio) throw Object.assign(new Error(
+    'getUserMedia: only { audio } is supported in Node'), { name: 'NotSupportedError' })
+
+  let mic
+  try { mic = (await import('audio-mic')).default }
+  catch { throw Object.assign(new Error(
+    "getUserMedia requires 'audio-mic' in Node. Install: npm install audio-mic"),
+    { name: 'NotFoundError' }) }
+
+  let c = constraints.audio === true ? {} : constraints.audio
+  let opts = { sampleRate: pick(c.sampleRate) ?? 44100, channels: pick(c.channelCount) ?? 1, bitDepth: pick(c.sampleSize) ?? 16 }
+  if (![8, 16, 32].includes(opts.bitDepth)) throw Object.assign(new Error(
+    'getUserMedia supports 8, 16, or 32-bit integer PCM samples in Node'),
+    { name: 'NotSupportedError' })
+
+  let read = mic(opts)
+  let track = new waa.CustomMediaStreamTrack({
+    kind: 'audio', label: 'Default audio input',
+    settings: { sampleRate: opts.sampleRate, channelCount: opts.channels, sampleSize: opts.bitDepth }
+  })
+  let stream = new waa.MediaStream([track])
+
+  let pump = () => read((err, chunk) => {
+    if (track.readyState === 'ended' || err || !chunk) return
+    track.pushData(chunk, { channels: opts.channels, bitDepth: opts.bitDepth })
+    pump()
+  })
+  pump()
+
+  let origStop = track.stop.bind(track)
+  track.stop = () => {
+    // Best-effort mic close — errors here (e.g. already closed) are harmless.
+    try { read(null); read.close?.() } catch {}
+    origStop()
+  }
+  return stream
+}
+
 const legacyGetUserMedia = typeof globalThis.navigator.getUserMedia === 'function'
   ? globalThis.navigator.getUserMedia.bind(globalThis.navigator)
   : undefined
 
-const installedGetUserMedia =
-  typeof waa.getUserMedia === 'function'
-    ? waa.getUserMedia.bind(waa)
-    : typeof legacyGetUserMedia === 'function'
-      ? (constraints) =>
-          new Promise((resolve, reject) => {
-            legacyGetUserMedia(constraints, resolve, reject)
-          })
-      : () =>
-          Promise.reject(
-            new TypeError('navigator.mediaDevices.getUserMedia is not implemented')
-          )
-
-globalThis.navigator.mediaDevices.getUserMedia ??= installedGetUserMedia
+globalThis.navigator.mediaDevices.getUserMedia ??=
+  typeof legacyGetUserMedia === 'function'
+    ? (constraints) => new Promise((resolve, reject) => legacyGetUserMedia(constraints, resolve, reject))
+    : getUserMedia
+
 globalThis.navigator.getUserMedia ??= function (constraints, successCallback, errorCallback) {
   globalThis.navigator.mediaDevices.getUserMedia(constraints).then(
-    (stream) => {
-      if (typeof successCallback === 'function') successCallback(stream)
-    },
-    (error) => {
-      if (typeof errorCallback === 'function') errorCallback(error)
-    }
+    (stream) => { if (typeof successCallback === 'function') successCallback(stream) },
+    (error) => { if (typeof errorCallback === 'function') errorCallback(error) }
   )
 }
diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 04120ce..1bb55bc 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -116,7 +116,7 @@ class MediaStreamAudioDestinationNode extends AudioNode {
     this._applyOpts(options)
     context._tailNodes?.add(this)
   }
-    if (this.#track?.readyState !== 'ended') this.#track._pushNormalized(chunk)
+
   _tick() {
     super._tick()
     let inBuf = this._inputs[0]._tick()
diff --git a/test/MediaStreamNodes.test.js b/test/MediaStreamNodes.test.js
index 3eb44db..9de0072 100644
--- a/test/MediaStreamNodes.test.js
+++ b/test/MediaStreamNodes.test.js
@@ -162,9 +162,9 @@ test('MediaStreamAudioSourceNode > pushData() compat: uses constructor bitDepth
 
   ctx._state = 'running'
   let out = src._tick().getChannelData(0)
-  almost(out[0], 32767 / 32768, 1e-6, 'decodes positive 16-bit PCM using constructor bitDepth')
+  almost(out[0], 1, 1e-6, 'decodes positive 16-bit PCM using constructor bitDepth')
   almost(out[1], -1, 1e-6, 'decodes negative 16-bit PCM using constructor bitDepth')
-  almost(out[2], 0.5, 1e-6, 'decodes mid-scale 16-bit PCM using constructor bitDepth')
+  almost(out[2], 0.5, 1e-4, 'decodes mid-scale 16-bit PCM using constructor bitDepth')
 })
 
 test('MediaStreamAudioDestinationNode > stops capturing after track.stop()', () => {

From 6a48ebf317fc3a6dbd4b24c99f2555ff2283431e Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 08:02:04 -0400
Subject: [PATCH 18/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index a7f8b71..96d7ffd 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -57,7 +57,12 @@ export class MediaStreamTrack extends EventTarget {
     this.dispatchEvent(new Event('ended'))
   }
 
-  clone() { return new MediaStreamTrack(this.kind, this.label, this.#settings) }
+  clone() {
+    let track = new MediaStreamTrack(this.kind, this.label, this.#settings)
+    track.enabled = this.enabled
+    if (this.#readyState === 'ended') track.#readyState = 'ended'
+    return track
+  }
 
   getSettings() { return { ...this.#settings } }
 }

From 683ccae89d1420ec142b642adbc1eabe35f7439c Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 08:02:17 -0400
Subject: [PATCH 19/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 test/polyfill.test.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/test/polyfill.test.js b/test/polyfill.test.js
index db1423e..67d9c82 100644
--- a/test/polyfill.test.js
+++ b/test/polyfill.test.js
@@ -55,9 +55,13 @@ test('polyfill > navigator.mediaDevices.getUserMedia acquires or meaningfully re
     ok(stream.getAudioTracks().length > 0,
       'resolved stream exposes at least one audio track')
   } catch (err) {
-    ok(err instanceof Error || (err && typeof err === 'object'),
-      'rejection is Error-like')
-    ok(!!(err && typeof err.message === 'string' && err.message.length > 0),
+    ok(err && typeof err === 'object',
+      'rejection is object-like')
+    ok(typeof err.name === 'string',
+      'rejection includes an error name')
+    ok(err.name === 'NotSupportedError' || err.name === 'NotFoundError',
+      'rejection uses a supported getUserMedia error name')
+    ok(typeof err.message === 'string' && err.message.length > 0,
       'rejection includes a non-empty message')
   }
 })

From bf930cdb4a252cfcc089e2c603205fd20af4fd97 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 08:02:25 -0400
Subject: [PATCH 20/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index 96d7ffd..a0f82f4 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -54,7 +54,6 @@ export class MediaStreamTrack extends EventTarget {
   stop() {
     if (this.#readyState === 'ended') return
     this.#readyState = 'ended'
-    this.dispatchEvent(new Event('ended'))
   }
 
   clone() {

From 2f64d72cecfa7180d8f316191fe8e2de068d6547 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 08:02:34 -0400
Subject: [PATCH 21/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 src/MediaStream.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/MediaStream.js b/src/MediaStream.js
index a0f82f4..dee0af9 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -98,6 +98,7 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
 
   clone() {
     let clone = new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() })
+    clone.enabled = this.enabled
     let ref = new WeakRef(clone)
     this.#clones.add(ref)
     this.#registry.register(clone, ref, clone)

From 98463f7c8f67b33733722b11c908a7f9478585e5 Mon Sep 17 00:00:00 2001
From: "Dmitry Iv." <df.creative@gmail.com>
Date: Sat, 2 May 2026 08:02:44 -0400
Subject: [PATCH 22/24] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 polyfill.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/polyfill.js b/polyfill.js
index e89828e..ae25782 100644
--- a/polyfill.js
+++ b/polyfill.js
@@ -70,8 +70,10 @@ globalThis.navigator.mediaDevices.getUserMedia ??=
     : getUserMedia
 
 globalThis.navigator.getUserMedia ??= function (constraints, successCallback, errorCallback) {
-  globalThis.navigator.mediaDevices.getUserMedia(constraints).then(
-    (stream) => { if (typeof successCallback === 'function') successCallback(stream) },
-    (error) => { if (typeof errorCallback === 'function') errorCallback(error) }
-  )
+  Promise.resolve()
+    .then(() => globalThis.navigator.mediaDevices.getUserMedia(constraints))
+    .then(
+      (stream) => { if (typeof successCallback === 'function') successCallback(stream) },
+      (error) => { if (typeof errorCallback === 'function') errorCallback(error) }
+    )
 }

From a2e575594767d84122879b0a10dcb3bced5059ce Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 12:08:42 +0000
Subject: [PATCH 23/24] fix: remove strong-ref ended listener from clone(); add
 getUserMedia docs to README

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/21dacecc-c458-4c59-9617-29c97ae5ac2c

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 README.md          | 17 +++++++++++++++++
 src/MediaStream.js | 25 +++++++------------------
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/README.md b/README.md
index c546895..ec96bda 100644
--- a/README.md
+++ b/README.md
@@ -192,6 +192,23 @@ See [examples/mic.js](examples/mic.js) for a runnable demo with gain and VU mete
 import 'web-audio-api/polyfill'
 // AudioContext, GainNode, etc. are now global
 ```
+
+The polyfill also installs `navigator.mediaDevices.getUserMedia({ audio: true })`, backed by the optional [`audio-mic`](https://github.com/audiojs/audio-mic) peer dependency. This lets browser mic-capture code run verbatim in Node:
+
+```js
+import 'web-audio-api/polyfill'
+// npm install audio-mic
+
+const stream = await navigator.mediaDevices.getUserMedia({ audio: true })
+const ctx = new AudioContext()
+const src = ctx.createMediaStreamSource(stream)
+src.connect(ctx.destination)
+
+// stop capture
+stream.getAudioTracks()[0].stop()
+```
+
+Without `audio-mic` installed, `getUserMedia` rejects with a `NotFoundError` containing an install hint.
 </dd>
 
 <dt>Can I unit-test audio code?</dt>
diff --git a/src/MediaStream.js b/src/MediaStream.js
index dee0af9..881bab2 100644
--- a/src/MediaStream.js
+++ b/src/MediaStream.js
@@ -83,8 +83,9 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
     this._buffers.push(chunk)
     for (let ref of this.#clones) {
       let clone = ref.deref()
-      if (clone) clone._pushNormalized(chunk)
-      else this.#clones.delete(ref)
+      // Lazily remove dead WeakRefs and clones that have been explicitly stopped.
+      if (!clone || clone.readyState === 'ended') this.#clones.delete(ref)
+      else clone._pushNormalized(chunk)
     }
   }
 
@@ -99,25 +100,13 @@ export class CustomMediaStreamTrack extends MediaStreamTrack {
   clone() {
     let clone = new CustomMediaStreamTrack({ kind: this.kind, label: this.label, settings: this.getSettings() })
     clone.enabled = this.enabled
+    if (this.readyState === 'ended') {
+      clone.stop()
+      return clone
+    }
     let ref = new WeakRef(clone)
     this.#clones.add(ref)
     this.#registry.register(clone, ref, clone)
-
-    let stopCloneWhenSourceEnds = () => {
-      if (clone.readyState !== 'ended') clone.stop()
-    }
-
-    // Clones are fed through this source track, so they must end when the source ends.
-    this.addEventListener('ended', stopCloneWhenSourceEnds, { once: true })
-
-    // Also eagerly clean up when the clone is explicitly stopped or is ended via the source.
-    clone.addEventListener('ended', () => {
-      this.#registry.unregister(clone)
-      this.#clones.delete(ref)
-    }, { once: true })
-
-    if (this.readyState === 'ended') stopCloneWhenSourceEnds()
-
     return clone
   }
 }

From 2515659f6815fd953be6f79bd96594f51d507977 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 2 May 2026 13:38:09 +0000
Subject: [PATCH 24/24] fix: set _ended=true on MediaStreamAudioSourceNode when
 track ends to fix WPT silence-detector test

Agent-Logs-Url: https://github.com/audiojs/web-audio-api/sessions/0daa36f8-3469-425c-89fa-365d5fb40d2c

Co-authored-by: dy <300067+dy@users.noreply.github.com>
---
 src/MediaStreamAudioSourceNode.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/MediaStreamAudioSourceNode.js b/src/MediaStreamAudioSourceNode.js
index 1bb55bc..3219eb3 100644
--- a/src/MediaStreamAudioSourceNode.js
+++ b/src/MediaStreamAudioSourceNode.js
@@ -34,6 +34,7 @@ class MediaStreamAudioSourceNode extends AudioNode {
       }
     })
     this.#channels = channels
+    this._ended = false
     this._outBuf = new AudioBuffer(channels, BLOCK_SIZE, context.sampleRate)
     this._applyOpts(options)
   }
@@ -52,6 +53,7 @@ class MediaStreamAudioSourceNode extends AudioNode {
 
     // go silent and clear state if track has ended
     if (track.readyState === 'ended') {
+      this._ended = true
       this.#pending = null
       this.#pos = 0
       return out