I'm pretty new to this whole home theater thing, trying to understand what I am sure are the most simple of things. But right now I'm getting very frusterated by a buzzing in my subwoofer. My system is a Onkyo HT-S780 with 7.1 surround. For some reason my subwoofer keep emitting a slight buzz sound that does not vary, no matter what I do. The only thing that stops it is if I unplug it. I have tried plugging it into different outlets, moving it away from other cords, and removing my cable cord - no difference. I would appreciate it if anyone could help me with this, I really don't have any idea what I can do. Right now I'm just turning up the volume loud enough so I don't hear it.. I think it's annoying my neighbors...