I have a B&K Reference 50 Preamp, Adcom GFA-5503 Amp, and definitive Tech BP7002 towers and a center running my front 3 channels of a 7 speaker system. now and then i here fuzzy static coming from the front right channel speaker when watching tv, dvd, raising and lowering vol.,and several sec. after changing a channel. What the hell is this. My connections are solid. is this a product of surround sound or is something wrong.