Comment 14 for bug 42600

I have a Dell latitude D520 and experienced this bug also.
After a **lot** of googling I came upon ALSA BUG #2038 ( https://bugtrack.alsa-project.org/alsa-bug/view.php?id=2038 ) that seems to dell with this bug. This problem seems to be related with ICH7, Sigmatel codecs (STAC 92xx, as one can see in /proc/asound/card0/codec#0), Dell BIOS not setting things up correctly and ALSA not working around this ;-)

The workaround, it seems, consists in adding "options snd-hda-intel model=ref" to /etc/modprobe.d/alsa-base. You may have to select the correct input source, though (gnome-mixer, options tab...). Also, make sure capture is not muted or with a volume level too low (again in gnome-mixer...) This worked in my Dell latitude D520 with ubuntu 6.06 LTS kernel (more precisely, 2.6.15-27-686). Skype works with alsa, sound recorder works, etc.

More recently I updated my BIOS to revision A02 AND compiled alsa-modules from alsa-source 1.0.11 (source from edgy). This setup seems to be working without the "model=ref" hack but I would need more time to verify that...

Well, I would suggest re-opening this bug, as this is clearly not fixed in the kernel shipped with 6.06. Yes, there's an easy workaround but this is far from the perfect solution - and it is not well documented.

Better yet would be collecting information about other notebooks/systems affected by this bug and submiting their PCI vendor, device and subsystem IDs and forwarding this to ALSA. I attached mine just for the record.

#include <bad_english_excuses.h>