Audacity crashes when "Software Playthrough" is enabled


I am using Audacity in Raspberry Pi 4 to do audio recording from a 6-mic device.
My problem is that Audacity crashes when “Software Playthrough” is enabled.
I want to debug it myself, and want to seek advice from expert in this forum.
Can anyone point me to some resource on how to do debugging?

The Audacity version in the the Pi, installed by using “apt install” command, is 2.2.2.

I also attach the diagnostic files generated by Audacity.

There is extra file called screen-log.txt, which is an screen output generated by Audacity when I started in in command line. The file catches error message when crash occurred.

6-mic device.

Do you expect to be recording from six microphones? Or do you have a stereo mixer with six inputs?

Audacity can be configured for multi-track recording but will only play stereo, two track, left and right.

Playthrough means that Audacity has to perfectly manage all it’s recording channels and all available playback channels as close as possible to the exact same time. It’s a stress on the machine. Audio doesn’t take a break like processing documents, pictures, or spreadsheets.

You should know that Playthrough is always late. If your intent is musical overdubbing, you have to do it with your recording device, mixer, or microphone and not the computer.

I used playthrough on a professional job by listening to playthrough with large headphones while the guest, interviewer, and the sound support people were performing live, some half-second earlier. I was playing quality control/recording engineer.


Hi Koz,

First, I appreciate your response.
Here is some background of my application. We try to build a sound recording prototype that is used in an clinical environment. We want to attach very small MEMS microphones to skin of a patient’s throat, who has swallow problem. The device will record patient’s swallowing sound when he is given fluid food. The swallowing sound may be too soft to be heard by doctor, that’s why we want Audacity to play it out through a plugin earphone simultaneously, so that doctor can do some marking. In fact my device has 2 more loopback channels that can be used to do playout.

I used the following method:
arecord -D hw:1,0 -f S32_LE -r 16000 -c 8 mono_to_play.wav & sleep 0.8 && aplay -D plughw:1,0 -r 16000 mono_to_play.wav

and it basically works. That small delay of playing is acceptable.

I hope I have made my objective clear. I am new to OS’s handling of sound devices, and not sure if there is better way.