[meta-bug] Inverted Internal microphone (phase inversion)
This is a metabug for all machines that are having phase inverted internal microphones.
If your internal mic is either completely silent (no signal), or you can possibly pick a very small sound, with much background noise, even though you have set gain to maximum, there is something you could try.
Install the pavucontrol application, start it and go to the "Input Devices" tab. Unlock the channels (there is a keylock icon), then mute the right channel while keeping the left channel at the volume you want.
If the internal mic is now working correctly, you have an inverted internal mic, so that your right channel cancels out the left one.
(If you're not running PulseAudio, you can try doing the same through AlsaMixer instead (see https:/
If so, please file a separate bug against the alsa-driver for your issue, make sure hardware info gets attached to it (either alsa-info as per https:/
As time permits, I'll try to work on fixing them for the next Ubuntu release. Thanks!
-- David Henningsson