I am running a pioneer 925k receiver from my pc to a 5.1 speaker setup. I ran the setup process where it tests the speakers and the subwoofer makes the appropriate noises but when I try to play sound from wmp or winamp, I can't get the sub to work. I am running sound with optical from the motherboard to the reiever. Much appreciated if someone could give me some advice on this one. I'm stumped