Just curious, how long have you had your setup? I recently got a used Musician ( not the II ) to drive speakers with Heil tweeters, which are like electrostatics. Although, so far most CDs sound much better, a few, 5-10 % sounded a little bright or strained like you suggest. But it seems that the more I play those CDs the more clear and detailed they become. I'm thinking that if I go back to the old amp, they might sound muddy now. Just a thought!
Sonny