"So when I left for work this morning, I threw some CDs in the CD changer, hit repeat, turned up the bass, turned the HK AVR230 up to about -18dB, and walked out the door. When I came home for lunch, a miracle had happened."

I did basically the same thing with my M22's and my HSU STF-2 with the same result -- the sound improved significantly in my absence. Since they were broken in -- there, I said it -- the sound has not continued to change. Not one bit.