i have a Sony STR-DE895 rated 100Wx5 @8ohms. I've been having issues with getting the SPL meter to get consistent readings to tweak my system. I can't get the meter to register above 60db. I measured each of my speakers (definitive technology ProCinema 80 system) and they are all 4ohm. I am wondering if this is the main cause of my problem. i have tried many things on the receiver and nothing helps, even cranking all the levels.. thanks.