I agree with end on this. From what you've described BP, it sounds like the fan may be going. Electric motors don't always just go completely when they do, sometimes it's gradual. I hope the new fan works for you guys and it isn't wiring or something else. All I know is you should have Muscle's destroyed, ground into fine powder, and buried before it infects the rest of us.

Really weird how both of you had the same problem at the same time...