Comment 37 for bug 195605

I confirm this occuring on the final Jaunty.
Made several test trying to figure it out.
On releases prior to Jaunty it's enough to
add this

"alias snd-card-0 snd-hda-intel
options snd-card-0 index=0
options snd-hda-intel model=vaio"

But, after upgrading the sound is still messy.

To solve you need to add (just in one line) the following

options snd-hda-intel model=vaio enable=1 index=0 position_fix=1 probe_mask=1

That should make switching back to normal.

Thanks to ubuntuforums.