As an Ubuntu core developer (volunteer/community), I generally garden bugs related to the Linux audio stack. Please note that I am not employed by Canonical but will attempt to address concerns as quickly as possible. Thanks for understanding my incredibly demanding non-Ubuntu schedule.
If you are experiencing audio problems in Ubuntu 9.04 (Jaunty) or later, please use "ubuntu-bug alsa-base" in a Terminal/Konsole.
Current Ubuntu/Debian work: patch review; StableReleaseUpdates packaging, tracking, and verification; audio stack integration; regression harness. I blog (quite) intermittently about this work at http://drowninginbugs.blogspot.com/search/label/ubuntu I dent (quite) intermittently about this work and other bits at http://identi.ca/crimsun