So the other day I had the house to myself and decided to play with the sub a little, and threw the Avia disc in, RS meter in hand.

With the test that alternates LF,S,C,S,RF,S,RS,S,LS,S, I noticed - and I'm sure that this behaviour is no different than what I'd tested before, but didn't really think about it then - that the C -> S test cycle yields mucho higher sub SPL than the other fronts do. Like about 10db higher. Went from 80db for LF -> S to just under 90 db for C -> S. I had to adjust the dial on the meter to the 90s.

Is this likely to be due to my crappy cheap AVR? The AVR was using the optical connection to the DVD player so any bass management setup in the DVD player shouldn't factor in. Avia quirk maybe?

Anyone experience anything similar? I'd appreciate any ideas about what might be causing this and what I should do about calibrating.