Great post Oz as always, glad that you find your M60s to your liking. I wish I would know the answer to your problem though. I have never noticed such with my system. I usually keep my volume level at my Rotel RC-1070 at 9-10 o'clock, as it already so loud. I have tried at 12" and it is sooooo loud without any distortion of any kind. I can only keep it there for up to ten seconds, as it painfully loud, and my nighbors would start calling the police.
I have my speakers exactely 18" from the wall. I have experienced a lot, and this is where the bass level seems to optimal for me. However, I have them only 6.5' apart, because of space limitations (a couch is in the way).
One more thing Oz: PICTURES!!!!
