I recently bought an Onkyo HT-S650 system. After working a long time with this system I noticed that the Bass-Treble controls only work on the front right and left channels! That was the cause of much of my problems since I was using treble boost which made the center channel sound muddy. My question is do ALL receivers have this problem (specifically Denons)? If not, is there anyplace in their specifications where this is defined?