Ubuntu – Microphone Volume changing randomly

Not sure if this applies to everyone, but if you use any kind of web conference / video chat service in Chrome / Chromium such as Google Hangouts, there's a good chance it uses the WebRTC protocol. Unfortunately the WebRTC implementation in Chromium comes with a handy “feature” called Automatic Gain Control that tends to screw with your microphone volume. Unless the web app itself gives you an option to disable it, there is otherwise no way turn it off, and Chrome developers don't want to add a global “off switch” for it.

What I ended up doing was to use @lelandbatey's solution. Since I was using PulseAudio, I used pacmd instead of amixer:

while sleep 0.1; do pacmd set-source-volume alsa_input.???-?????.analog-stereo 90000; done

Note that 65535 corresponds to 100%, so 90000 is about 135%. The name of the device (alsa_input.???-?????.analog-stereo) should be substituted with whatever you find by running pacmd list-sources | grep name::

name: <alsa_input.???-?????.analog-stereo>

I had the same issue. I was able to fix it using the following steps:

1. Removed ~/.config/pulse directory.

2. Started Pulse Audio.

   rm -rf ~/.config/pulse
   pulseaudio --start
   

Incase if its still showing errors you will have to reinstall pulse audio and equalizer.

sudo apt-get purge pulseaudio pulseaudio-equalizer
sudo apt-get install pulseaudio
sudo apt-get install pulseaudio-equalizer
pulseaudio --start