Rich_D

Yeah, that was me starting to disassemble before I remembered to take pics for reassembly and to post here.

Yeah I have a schematic for it. Thanks for all the tips. I wasn't thinking power supply because I have all lights and power but I really don't know much about these circuits.

Ok thanks, I'll start an Ebay watch. I can't bring myself to throw away all this electronics though. Maybe I can see it for parts/repair.

I have a very old ProMedia 2.1 THX system, see pics. It has the original preamp input which has actually never given me problems, nor has the control module. Upon moving it from one room to another, when I power on the system I get a very loud thump or whomp sound from the sub. It's rhythmic like a steady heartbeat. Support said it's in the amp but it's too old and unserviceable. I have the circuit boards apart but I don't see any problems from visual inspection. Caps look ok. Can anyone direct me where I might start looking for the problem?