I’ve recently installed Ubuntu Jaunty on an HP Pavilion dv6-1110ss and everything I tried worked fine except for one thing: there was no sound.
After searching for a while and trying out some stuff, the solution is easy. Just open file /etc/modprobe.d/alsa-base.conf and add the following lines:
options snd-pcsp index=-2
alias snd-card-0 snd-hda-intel
alias sound-slot-0 snd-hda-intel
options snd-hda-intel model=hp-m4
options snd-hda-intel [...]