I have two crown XTI4000s and they have both had the recalled part replaced. However, they both still cut in and out, either allowing for no sound, or changing the sound volume.
One of them just got the full main board replaced. (the other's new board is on order) the one with the new board is now still waffling on the sound - gets louder for no reason and then goes back to regular (both music and mics). We plugged in an old random amp in to same speakers/board/etc and it is fine.
I have upgraded the firmware on the amp to the latest, and have the keys in the front locked down so it's not getting bumped.