(
Edit: Before you attempt any change on your system, could you check first that your sound isn't simply muted? Run the commands
alsaconf and
alsamix. And there should be something like "volume control" in
System > Preferences or
Administration, or simply by double-clicking on the speaker icon on your desktop)
If your sound is not muted, there are two links that I can suggest to you. The first one:
http://linuxtechie.wordpress.com/200...work-in-gutsy/
suggests the upgrade of ALSA to the most recent version. It might work for your card. The second one:
https://help.ubuntu.com/community/HdaIntelSoundHowto
Is a much more detailed HOWTO for fixing various sound problems on Ubuntu. It's a fairly long read but it's worth going through it; especially "Manually Specify Module Parameters", in case upgrading ALSA doesn't do the trick.