Okay, get this. The room in question was a room we never really listened to with any kind of volume much above 16 or 20. The other day was the first time really that we listened to music above that volume and that is when we heard the problem. That is why I was trying to find out what had happened. I have been looking for answers but nobody seemed to have any that made any sense. I have been scrambling for answers to the point of even thinking of replacing the wire which would have been a major undertaking. After checking the speakers wiring from the Cav to make sure all was correct I went down to the Cav and all the wiring on the back of the Cav was the same. I then just for the fun of it decided to move the positive and the negative around and just switch them. You would not believe it. The problem went away. The wiring on the Cav must be screwed up on that zone. It now works after I put the wires in the wrong places.