Installed David's dkms package (had to install dkms as well) and after rebooting the issue was resolved.
** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/882693 Title: [OptiPlex XE] Rear audio out port does not mute internal speakers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/882693/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs