Comment 1 for bug 275289

Thank you for your bug report. What version(s) of Mythbuntu did you try? If you haven't already, would you be able to try either the current alpha release of 8.10, or the beta release (coming out late next week)?

Some random debugging links and info:
It seems this particular Realtek audio chip has been somewhat problematic, both pre 8.04: http://ubuntuforums.org/showthread.php?p=4653915, and post 8.04: http://ph.ubuntuforums.com/showthread.php?t=856390. To make matters worse, there appears to be two versions of that chip (http://ubuntuforums.org/showthread.php?t=877815).

Depending on the exact problem, http://ubuntuforums.org/showthread.php?t=877815 has a possible solution. There are other hits in launchpad and the forums as well.