I have a 2 year old Synergy sub 10 subwoofer. It's connected to the LFE/Left connection to a Yamaha receiver. The sub is set to auto and wakes appropriately (as indicated by the blue LED), but no sound comes out. I ran test signals to the speakers and no sound was hitting the sub. The wiring checked out fine. I turned the gain all the way up, still no sound. Suggestions?!?! Time for a new sub?

Interesting.  Mine is hard to awaken.  You really have to crank up the main amplifier to get the sub to resurrect.  Once it is on, everything is fine and you can return to normal volume.  I'm sure there must be an adjustment somewhere.  Maybe someone can help us both.

DRBILL