I have the new MTH CP 6644 (20-21499-1) and am having some issues. First off, the smoke control 'knob' doesn't do anything. I generally run without smoke so I just turn it all the way off, but the smoke unit does not go off. Wasn't really something I was worried about as I could just open it up and disconnect the smoke unit and be done. But now sometimes while running the sound gets all garbled or cuts out. I don't know a lot about these, so I don't know if they are related or not (Like a board is going out or not.), or if there is a simple fix I can do or do I have to send it back to MTH for repair. Can I even send it back to MTH at this point to get fixed? My LHS that did MTH repairs is long gone sadly.