I just picked up an Onkyo HT-SP904 HTIB which has the HT-557 receiver from Frys for 499 seems like a good deal after shopping around on internet. I plan to upgrade the speakers and sub as I can. I feel the receiver is all i need. But I've noticed some speaker buzz at medium to high volume levels and its really annoying. My source al all sound is my HTPC connected through good old lossless analog (headphone to stereo RCA cable X 3) when i mute the computer the buzz continues but when i mute the receiver the buzz stops. Any suggestions? Does this HTIB just suck?