So, now I know "the rest of the story"... My wife had a birthday party for her girlfriend and she had all the girls over and were playing the stereo "real loud" for "a while". I asked her to define those loose terms. She said they had it going for over an hour and had it loud enough so they could 'hear the music outside' which is where they were hanging out... mind you that was the other side of the house. So, I suspect the clipping theory is the most likely one.

Knowing that, I am now concerned that the M22's could have been damaged at this gala event... Any way to test them to determine if any damage has occurred?. Ditto on the subwoofer.

Now it's a case of what option to choose.... Replace the blown drivers, get a new VP180 to replace the VP150, get a new receiver able to withstand her onslaughts, or a new amp to drive the center channel.