Just performed a fresh install and sound plays from the speakers but not from the headphones. No sound at all. If I pull the jack out, then push it in slightly, it works but sound plays from the speakers also.
lspci | grep -i audio
00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02)
I am using an MSI Wind u100 netbook. F