diff --git a/Tutorials/learn-monogame-2d/src/15-Audio-Controller/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/15-Audio-Controller/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/15-Audio-Controller/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/15-Audio-Controller/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/16-Working-With-SpriteFonts/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/16-Working-With-SpriteFonts/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/16-Working-With-SpriteFonts/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/16-Working-With-SpriteFonts/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/17-Scenes/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/17-Scenes/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/17-Scenes/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/17-Scenes/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/18-Texture-Wrapping/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/18-Texture-Wrapping/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/18-Texture-Wrapping/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/18-Texture-Wrapping/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/19-User-Interface-Fundamentals/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/19-User-Interface-Fundamentals/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/19-User-Interface-Fundamentals/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/19-User-Interface-Fundamentals/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/20-Implementing-UI-With-Gum/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/20-Implementing-UI-With-Gum/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/20-Implementing-UI-With-Gum/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/20-Implementing-UI-With-Gum/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/21-Customizing-Gum-UI/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/21-Customizing-Gum-UI/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/21-Customizing-Gum-UI/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/21-Customizing-Gum-UI/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/22-Snake-Game-Mechanics/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/22-Snake-Game-Mechanics/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..13ba764c 100644
--- a/Tutorials/learn-monogame-2d/src/22-Snake-Game-Mechanics/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/22-Snake-Game-Mechanics/MonoGameLibrary/Audio/AudioController.cs
@@ -97,21 +97,21 @@ public AudioController()
 
     /// <summary>
     /// Updates this audio controller
-    /// </summary>
+        /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/23-Completing-The-Game/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/23-Completing-The-Game/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/23-Completing-The-Game/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/23-Completing-The-Game/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/24-Shaders/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/24-Shaders/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/24-Shaders/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/24-Shaders/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/25-Packaging-Game/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/25-Packaging-Game/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/25-Packaging-Game/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/25-Packaging-Game/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/26-Publish-To-Itch/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/26-Publish-To-Itch/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/26-Publish-To-Itch/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/26-Publish-To-Itch/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }
 
diff --git a/Tutorials/learn-monogame-2d/src/27-Conclusion/MonoGameLibrary/Audio/AudioController.cs b/Tutorials/learn-monogame-2d/src/27-Conclusion/MonoGameLibrary/Audio/AudioController.cs
index 1bffd636..02a5759b 100644
--- a/Tutorials/learn-monogame-2d/src/27-Conclusion/MonoGameLibrary/Audio/AudioController.cs
+++ b/Tutorials/learn-monogame-2d/src/27-Conclusion/MonoGameLibrary/Audio/AudioController.cs
@@ -100,18 +100,18 @@ public AudioController()
     /// </summary>
     public void Update()
     {
-        int index = 0;
-
-        while (index < _activeSoundEffectInstances.Count)
+        for (int i = _activeSoundEffectInstances.Count - 1; i >= 0; i--)
         {
-            SoundEffectInstance instance = _activeSoundEffectInstances[index];
+            SoundEffectInstance instance = _activeSoundEffectInstances[i];
 
-            if (instance.State == SoundState.Stopped && !instance.IsDisposed)
+            if (instance.State == SoundState.Stopped)
             {
-                instance.Dispose();
+                if (!instance.IsDisposed)
+                {
+                    instance.Dispose();
+                }
+                _activeSoundEffectInstances.RemoveAt(i);
             }
-
-            _activeSoundEffectInstances.RemoveAt(index);
         }
     }