Once. At the NJ meet where somebody asked to borrow my empeg to see how a smoke lense would look in his car. I was like, "Yeah, fine", completely forgetting that I keep my volume locked at -3dB because I feed it though another HU.

There was some panic as the whole car virtually jumped off of the ground, followed by more panic when the volume knob didn't appear to be working. I can't remember who it was though...