Comment 9 for bug 914290

The next thing I would try is using different models in /etc/modprobe.d/alsa-base.conf

For example, add this line:
options snd-hda-intel model=dell-s14

and then reload alsa:
sudo /usr/sbin/alsa force-reload

STAC92HD83*
===========
  ref Reference board
  mic-ref Reference board with power management for ports
  dell-s14 Dell laptop
  dell-vostro-3500 Dell Vostro 3500 laptop
  hp HP laptops with (inverted) mute-LED
  hp-dv7-4000 HP dv-7 4000
  auto BIOS setup (default)