I am currently running Compiz as a standalone wm with xfce4-panel. I've managed to figure everything out except for sound control. ALSA and PulseAudio are both working fine but muting and unmuting has been challenging. First I tried using acpid to adjust the volume. It worked when raising or lowering the volume but when I pressed the mute button, it would mute but not unmute even though the LED would alternate between on and off every time I pressed it. Using pavucontrol, I figured out that this meant the master volume would respond but the speaker would get muted the first time and would stay muted. I tried using the same command that I associated with the event in acpid ("/usr/bin/amixer set Master toggle") from the command line and it worked correctly. Next I tried xfce4-mixer but this displayed the same behavior as acpid: conflict between speaker and master volume when muting. Finally I tried xbindkeys, again with the same amixer command, and it works without any trouble. What seems to be the difference between acpid/xfce4-mixer and xbindkeys/command line?