On a fresh Xubuntu install today I installed
fglrx-updates-dev and, after restarting, everything worked fine apart from audio. The volume indicator is greyed out and there are no sound options to be found anywhere. I installed pavucontrol and xfce4-mixer but neither of them will open, and every time I try to play a song, the music player (I've tried VLC and gmusicbrowser) either freezes or sits at 0:00. Firefox hangs and eventually needs to be forced closed if I try to watch a video on Youtube or elsewhere.
lspci | grep Audio returns the following:
00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05) 01:00.1 Audio device: Advanced Micro Devices [AMD] nee ATI Device aab0
EDIT: I'm using a Radeon HD 7750 card. I'm not using the HDMI audio from it, but two speakers that are plugged into the port for the onboard audio.