After a week of googling, I'm still no further forward on this and I haven't found ant evidence of anyone getting sound working with this motherboard on Linux.
However, I have discovered that it is actually playing sounds, just very, very quietly. With everything turned up high, and ear pressed to speaker, you can just hear the sounds (speakers and amplifier test out fine with a pci soundcard in the same machine). Does this shed any light to anybody ... help! -- Sound doesn't work on A8V-MX (VIA8233) https://launchpad.net/bugs/82021 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs