Speaking in a voice channel/voice call in the Linux desktop app causes the volume of my mic to lower by itself

This feature bothers me so much. I've never found a way to disable it; for me, gain control options do nothing. I've had to write a cron job to set all microphone levels back to 80% every 30 seconds so it doesn't creep down to inaudible levels.

Assuming it's not been deprecated, Electron should have a launch flag like --disable-features=WebRtcAllowInputVolumeAdjustment to disable it that you could try