I did some more searching and there were reports that there's a combination of Denon receivers, MPS-1 amps and low impedance speakers that could cause the amp to shutdown before appearing to develop rated power. I think that is why I got info stuck in my head that they didn't play well together. It seems that the nominal output voltage of the Denon preouts is something like 1.2V, which is a little lower than average. Throw in some possible clipping when cranking up the volume and the protect circuit on the amp kicks in when combined with a high current load.
But, the amp itself was doing its job and protecting the speakers - and it only happened when trying to generate absolutely insane SPL's . Also, the IPS and LPA amps don't have the same circuit and wouldn't be affected. (Of course, the speakers might melt their coils but at least you wouldn't be inconvenienced by a "premature" shutdown). Based on what I found, the Denons would be terrific pre-pros for anybody who wasn't courting early hearing loss.
Sorry for the scare everyone.
