Comment 7 for bug 1310622

I had the same problem, and realised that it may be caused by a previous try to solve a sound problem.

The solution would be:

1. Upgrade to the last Ubuntu version to date

2 edit the file (with admin rights):
/etc/modprobe.d/alsa-base.conf

Find the line:
# Keep snd-pcsp from being loaded as first soundcard
#options snd-pcsp index=-2
options snd-hda-intel model=laptop-eapd

And change to
# Keep snd-pcsp from being loaded as first soundcard
options snd-pcsp index=-2
#options snd-hda-intel model=laptop-eapd

Save the changes and reboot.
This solved the issue for me.