@CatBrat:

Thanks for the info! The AVR was an open box purchase but arrived in new condition. Unfortunately I've already tried messing with treble and the built-in equalizer which helps somewhat, but still the shrillness is there. Also I did run the sound EQ with the microphone it came with, but it didn't help much. Yeah I agree, if it is the AVR to blame then I'm in trouble. I figured I'd try better speakers first then if the issue remains I can be reasonable sure it's the AVR

@MarkSJohnson:
heh, I had to google to figure out what a Trip Ring Sleeve was (trs are my initials but hey I learned something new wink So you're thinking it's the AVR too. Good to know, over on avsforums some people were thinking it was the speakers, but then again they all had higher-end speakers like Paradigm, etc.