Well, I received the 7 channel Sherbourn yesterday and it is a beautiful piece of machinery. Set up was easy but when I fired it up I noticed one of the channels wasn't working so I rebooted it and all the channels began to work after the reboot. I was in 7th heaven until this evening when my fiance and I sat back to watch Harry Potter. During the quiet passages she noticed a buzz in the rear speaker. I stopped the DVD Player and went to check all of the speakers with the volume of the 4802 I am using as a pre/pro set to -30 (a low listening level). All of the speakers had a buzzing noise emitting from what seems to me to be the tweeters. I had t0 put my ear very near to the speaker to hear the buzzing. Is this normal for an amp? Should I be concerned enough to return the 115lb. beast? Opinions and experiences about this are very welcome.