Comment 24 for bug 1351916

Yaay! i found a workaround! It seems that the mic isn't correctly detected. What i did was:

sudo echo "options snd-hda-intel model=dell-headset-multi" > /etc/modprobe.d/snd-hda-intel.conf

and the mic started to work after a reboot. if it didn't work for you, you may try replacing " dell-headset-multi " with
" headset-mic " , " alc271-dmic " or any other mic model from https://www.kernel.org/doc/Documentation/sound/alsa/HD-Audio-Models.txt that is assigned to your audio card.