Hello Olivier! You and your code are amazing! And yes, compiling from source. I made the change in pyomodule.c and here's the error messages now. Please note that I am still able to run my main pyo program that doesn't us SfPlayer without problems.
Starting program: /usr/bin/python sfplayer_test.py
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
[New Thread 0x72108440 (LWP 2024)]
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
[Detaching after fork from child process 2025]
jackdmp 1.9.17
Copyright 2001-2005 Paul Davis and others.
Copyright 2004-2016 Grame.
Copyright 2016-2021 Filipe Coelho.
jackdmp comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
JACK server starting in realtime mode with priority 10
self-connect-mode is "Don't restrict self connect requests"
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
audio_reservation_init
Acquire audio card Audio0
creating alsa driver ... hw:audioinjectorpi|hw:audioinjectorpi|1024|2|48000|0|0|nomon|swmeter|-|32bit
configuring for 48000Hz, period = 1024 frames (21.3 ms), buffer = 2 periods
ALSA: final selected sample format for capture: 32bit integer little-endian
ALSA: use 2 periods for capture
ALSA: final selected sample format for playback: 32bit integer little-endian
ALSA: use 2 periods for playback
[New Thread 0x72087440 (LWP 2031)]
Pyo warning: Jack server started.
Pyo warning: Sample rate set to Jack engine sample rate: 48000.
Pyo warning: Buffer size set to Jack engine buffer size: 1024.
[New Thread 0x6b89e440 (LWP 2032)]
JackEngine::XRun: client = pyo was not finished, state = Running
JackAudioDriver::ProcessGraphAsyncMaster: Process error
[Thread 0x6b89e440 (LWP 2032) exited]
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
JackEngine::XRun: client = pyo was not finished, state = Triggered
JackAudioDriver::ProcessGraphAsyncMaster: Process error
Thread 3 "python" received signal SIG32, Real-time event 32.
[Switching to Thread 0x72087440 (LWP 2031)]
__libc_read (nbytes=4, buf=0x72086cbc, fd=5) at ../sysdeps/unix/sysv/linux/read.c:26
26 ../sysdeps/unix/sysv/linux/read.c: No such file or directory.
(gdb) backtrace
#0 __libc_read (nbytes=4, buf=0x72086cbc, fd=5) at ../sysdeps/unix/sysv/linux/read.c:26
#1 __libc_read (fd=5, buf=0x72086cbc, nbytes=4) at ../sysdeps/unix/sysv/linux/read.c:24
#2 0x76061e78 in () at /usr/lib/arm-linux-gnueabihf/libjack.so.0
#3 0x76065878 in () at /usr/lib/arm-linux-gnueabihf/libjack.so.0
#4 0x7606569c in () at /usr/lib/arm-linux-gnueabihf/libjack.so.0
#5 0x7606096c in () at /usr/lib/arm-linux-gnueabihf/libjack.so.0
#6 0x76f79300 in start_thread (arg=0x72087440) at pthread_create.c:477
#7 0x76e0b208 in () at ../sysdeps/unix/sysv/linux/arm/clone.S:73