In my previous post i have said that internal mic was not working on my Sony Vaio CS with Ubuntu. Look here. Now we have a solution.
Open the file /proc/asound/card0/codec#0. If you find Codec : Realtek ALC262 (first line), go to the next step.
Edit alsabase.conf, for that type :
sudo gedit /etc/modprobe.d/alsa-base.conf in a terminal.
at the end of the file add the following line
options snd-hda-intel model=toshiba-s06
Reboot and the internal mic should work.
credit to magic-neophyte, look here.
