In Ubuntu 12.04, after performing an upgrade that included a kernel update, I no longer have any sound. The sound worked fine before the upgrade. Oddly enough, if I plug in headphones I do get sound through the headphones, but without them I am no longer able to get any sound from my laptop's internal speakers.
I'm not quite sure what additional info I should provide, so here's some info to start. Please let me know if there is anything else I should add.
Laptop: HP Pavilion DV6
OS: Ubuntu 12.04 (Precise Pangolin) 64-bit
$ lspci | grep Audio
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)
$ uname -r
Many thanks in advance for any help!