Interestingly, on mine, I tried the 2:00/2:00 suggestion and it is a significant reduction in volume from the volume with nothing plugged into the loop. I listened very carefully and plugged/unplugged/plugged/unplugged the loop over and over. To carefully match the volume levels with the loop and without, I have to almost dime both controls. Anything less than almost all the way up on both, is a volume reduction from when there is no loop. I need to check the loop tube... but it has been that way since I got it. Heck, with both at 2:00 I can run both channel masters at noon at home. With nothing in the loop, that would be immediate visit from the wifey, or when she's not home and I do it, it literally tickles my ear drums at that volume.