I was having a bunch of issues with 11.10, my AMD graphics card and HP laptop so I reverted to 11.04 thinking now I would be able to focus on work.
After the re-install, my headphone jack is no longer detected. It works when I boot the computer with the jack already in, but if I take it out after the boot it doesn't work. If I don't have it in at boot, it won't work when I put it in until a reboot.
If I'm playing music through the internal laptop speakers and put the jack in the music will continue playing through the laptop speakers and not transfer.
Here's a link to the same question asked on UbuntuForums.org: http://ubuntuforums.org/showthread.php?p=10764275
