Comment 9 for bug 930617

i was able to fix this by googling for my brand / model of laptop and 'ubuntu'

ubuntu hp dv6 sound

there are numerous forums that list procedures to fix, typically by editing /etc files

i did several of them and now it works.

this was added to /etc/modprobe.d/alsa-base.conf

     alias snd-card-0 snd-hda-intel
     alias snd-slot-0 snd-hda-intel
     options snd-hda-intel model=dell-m4-3 enable_msi=1

and this was edited into /etc/pulse/default.pa (replacing the old udev line)

load-module module-udev-detect tsched=0