Eu experimentei o mesmo problema, encontrei este e resolvi o problema para mim.
If your microphone volume creeps up automatically and causes the sound to be distorted, you can fix it by disabling mic boost:
In
/usr/share/pulseaudio/alsa-mixer/paths/analog-input-internal-mic.confand/usr/share/pulseaudio/alsa-mixer/paths/analog-input-mic.conf,
- Under
[Element Internal Mic Boost]setvolumetozero.- Under
[Element Int Mic Boost]setvolumetozero.- Under
[Element Mic Boost]setvolumetozero.Then restart PulseAudio:
pulseaudio -k