Have a question about the safety of my setup. I have two systems, a living room with receiver and 5.1 and a "movie" room set up with 5.1. I have the receiver outputs for the fronts in the living room connected to a speaker selector, and the selector output going to the fronts in both rooms, so I can play music through the whole house. So the speakers in the movie room have inputs coming from the receiver/ speaker selector in the living room and from the receiver in the movie room. (These speakers have the two inputs, which is for bi-amping or something, so they are not on the same post, although I don't think that makes is safe.... I think). Anyway, I thought the speaker selector would keep me safe, but I'm beginning to doubt it now. When I play a show in the movie room the sound plays through the speakers in the living room. Doesn't make sense to me since the movie room speakers are essentially reversing it's role and becoming an input for the speaker selector if that makes sense. It's an output for the speaker selector, it shouldn't logically be playing sound on the outputs of other speakers. I've had both speakers on at the same time, not really intentionally, but it happened. I did hear a low frequency and very quiet hum from both speakers, which went away when I turned off one of the receivers. I read up and figured it was a ground loop (also don't fully understand that), but it's what it sounded like. Anyway, is what I'm doing okay? Thanks, and sorry for the long first post.