has anyone had a problem with loosing subs and hi end distortion? I unplug machine and do room perfect again and it sounds great for a while ,then back to weird things.when you first turn it on, Sometimes volume is to lower than it should be at 24 percent I have to go to center trim ,trim up to two or three and bang it's back to normal vol. Then I put back to 0 and the vol stays the same.I have been unplugging it to try to keep it stable. I originaly had mx 150 and had same issue ,that's why Mcintosh swapped out to the mx 151! Any input would be helpful.