Someone suggested I stuff a sock (or something) in the ports of the 3 upper M22's to dampen the bass. You know that's such a stupid sounding idea, but it just might work. I'll have to give it a go, then recalibrate, and see how it sounds.
So far, I'm liking the results of Pioneer's MCACC a whole lot better then Denon's Audyssey. It always sounded good with MCACC, not so with Audyssey, so far, but maybe I've gone beyond Audyssey's (and MCACC's) ability to handle it with my particular speaker arrangement. The funny part is, when I turn Audyssey off, I couldn't hear a difference.