Just started to... not much change. I was able to dial down the trim by 1 or 2 dB per channel and still hit 73dB with the test tone. Got the CD player back and ran some 2 channel tests, in stereo and bypass. Bypass doesn't drop in level as it did before and I can run high 80's low 90's on the SPL meter. Running in the mid 80's on the couple of movies I tested. With all of those tests, I do notice a brighter (bordering on harsh) sound as compared to my previous receiver... and even compared to almost maxed out volume at the 4ohm setting... but then again, I didn't get quite the same volume levels at the 4ohm setting I'm getting now. Haven't had a chance to try the DVD-based music videos yet to see if there's been a change.