I remember reading about your issues with the MPS. Of course their website says that all their amps will handle 4 amp loads fine and down to 2 amp loads. Something wasn't right if your speakers kept shutting down. Even down to 2 amp load, it shouldn't have lasted more than a few seconds at a time. I really like the XPA-5 so far but I want to see how it performs over a longer period of time.