I posted this in electronics, too, but they're a small group so I thought maybe someone here could help!
Anyway: I have this speaker control for a logitech z2300 speaker set. it handles everything and plugs into the sub with a DSub connector.. this page explains it well in pictures.
http://blog.jseaber.com/2010/02/27/logitech-z-2300-control-pod-disassembly/
Something is loose at the connection to the sub with the DSub connector. I'm pretty sure it's just a loose solder to one of the pins. I doubt it's the male side, but I can't be sure....
This is my 2nd instructable and I still need practise on MLCAD so please dont give me a hard time :D