Program stop decoding after beacon detection

[HB9DUT]

Works great on Ubuntu but has an Issue on RPI 3 with Raspian Buster:
Distributor ID: Raspbian
Description: Raspbian GNU/Linux 10 (buster)
Release: 10
Codename: buster

Program stops decoding immediately after beacon detection:

./qo100websdr

Webserver Path: /var/www/htmlcopy Web Site files to: /var/www/html
SDR parameters:

SDR base QRG: 433250000 Hz
SDR sample rate: 1800000 S/s
WF width: 900000 Hz
WF width: 1500 pixel
1st downsampling:1800000 S/s
1st decim. rate: 1
1st FFT resol.: 600 Hz
1st FTT smp/pass:3000
found 4 cores, running FFT in multithreading mode
OK: catproc started

Initialisation complete, system running ... stop with Ctrl-C
Waiting for incoming connections...
found 1 RTLSDR devices
Device: Generic RTL2832U OEM

Found Rafael Micro R820T tuner
accepted client 0 4
Connection opened, client: 4 | addr: 192.168.1.51
1 users logged in
[R82XX] PLL not locked!
Setting gain to: 49.60
=== [R82XX] PLL locked, OK ===
Allocating 15 zero-copy buffers
*Beacon found at pos:2726 diff:274 -> 27400 Hz
Beacon found at pos:2726 diff:274 -> 27400
rtl hz : 27400
rtl qrg : 433222600
rtl qrg corr: 2133
[R82XX] PLL not locked!
rtl rf : 2133_

[HB9DUT]

Declare RTL_TUNER_CORRECTION as float in rtlsdr.c solves the problem:

Line 77
unsigned long tqrg = (TUNED_FREQUENCY * (1000000L + float)RTL_TUNER_CORRECTION))/1000000L;

Line 138
qrg = (qrg * ((1000000L + (float) RTL_TUNER_CORRECTION) / 1000000L));`

...
*Beacon found at pos:2991 diff:9 -> 900 Hz
Beacon found at pos:2991 diff:9 -> 900
rtl hz : 900
rtl qrg : 433249100
rtl qrg corr: 433223072
rtl rf : 433223072
*Beacon found at pos:2987 diff:13 -> 1300 Hz
Beacon found at pos:2987 diff:13 -> 1300
rtl hz : 2200
rtl qrg : 433247800
rtl qrg corr: 433221792
rtl rf : 433221792
...