I just intstalled my HK AVR-7000. I set up 2 front and 2 surround speakers. When put into surround mode, I want all 4 speakers to play. Only the "theater" setting works. As for the other settings, (hall, vmax, dolby logic 7 . . . ) either only 2 front speakers works or when all 4 speaker is working, the volume goes up and down. What is this? Why does the volume do this? (I'm playing CD's setting on my DVD player) I would like to use my reciever up to its full advantage.