I have recently installed 12.04, but the sound is not working from both internal speakers, and from headphones when I connect them.

I have followed the instructions at https://wiki.ubuntu.com/DebuggingSoundProblems to no avail and submitted a bug report. I've also tried running alsamixer and unmuting a few more things, but that didn't work.

I've tried to upgrade alsa sound drivers by running:

sudo add-apt-repository ppa:ubuntu-audio-dev/ppa

sudo apt-get update

sudo apt-get install linux-alsa-driver-modules-$(uname -r)

however on the last command:

$ sudo apt-get install linux-alsa-driver-modules-$(uname -r)

Reading package lists... Done

Building dependency tree       

Reading state information... Done

E: Unable to locate package linux-alsa-driver-modules-3.2.0-24-generic-pae

E: Couldn't find any package by regex 'linux-alsa-driver-modules-3.2.0-24-generic-pae'

What should I do to try get sound functioning?

It might be worth noting that 10.04 previously ran on this machine with no sound problems.