I have just purchased an 8 inch Engery sub to go with my 5 speaker system on a Marantz SR 5200. For what its worth the other speakers are Mission M71's, with the accompanying Mission centre and surrounds. I just hooked up the sub and it does not seem to get enough power from the Marantz. I have to turn the sub up all the way on the sub's own controls before I hear anything, and the sound seems wrong and hollow. I have the Marantz set to read a sub. But I do notice that the sub light never turns on on the display. the LFE light does, but not the sub. Am I missing something? Is this a known problem with Marantz's?