OK, I did play around with the cables a bit. Yes, the pumping did switch sides when I reversed the inputs, although I did notice some pumping in both the front right & left BUT more so the left. When I reversed the inputs, it was more on the front right. When I reversed the inputs & outputs, it stayed mostly in the front left. As I said before, this is in 5.1 involve mode. When I go to 4.1, the pumping is greatly deminished.I'll try it when I get a chance.