Someone else got a good pic... although mine's balck:
So that's a toroid transformer, eh? Big bugger.
From the generically-named "Computer Forum" (http://www.computerforum.com/152154-...ing-out.html):
Originally Posted by jceb
I had same problem. Thought it was a heat tbl. I had to remove the speaker to get at circuit board underneath. On that board is a black relay and diode combo, about 2inches square which can be affected by heat. Labeled Massouse-ME 140FF 012-2h 12v DC. I noticed that just by touching this it would cause the sub to switch on and off. It turned out 1 of the 6 leads had a cold solder joint on back of board. A slight dab of solder fixed this aggrivating problem. NOte. It was easier using a walkman or such as a input to the green and tuning to an off station. That way you can work on table or bench.
... so it might not be the toroid transformer.. hmm... AFAIK though there's only one PCB in the sub's box; I don't recall seeing another one "underneath the speaker"...
EDIT: Ahh, I see... http://picasaweb.google.com/krislema...stemSubWoofer#
... there IS another PCB in there...