I use S/PDIF out and use Spaces with iTunes on "screen 2". Is there a way to setup a hotkey so I can adjust the volume of iTunes? Would like to assign F10 and F11 since they don't function with S/PDIF anyway. I see in itunes you can use Command Up and Down to adjust volume. However this only works when the program is active. How can I assign this (and change keys) so it works no matter what program is active (or no matter what screen I'm in)?