I have a cheap remote control for my computer. It has mouse and keyboard functions. The problem is that when I press volume + / - or mute on my remote control, I can see the notification at the top right corner of the desktop, but the sound doesn't actually change in any application (Songbird, SMPlayer, Totem etc). May be the media keys control the wrong channel/mixer, I don't know.
I am using Pulse Audio with ALSA mixer and Creative SB Audigy.