Well, I did turn the main power switch on the back of the sub off/on and it seemed to have stopped. Almost like energy was stored up and I released it.

I just ran down again, and still hear a very faint thump thump now and then. Is it possible if it is lightning outside that the ep600 could be picking up that energy, or could air preassure because of a storm move the woofer in/out enough to cause a faint thump. It is almost like if you took your finger and tap the driver cone.

Mojo, I'll try the coax cable next...

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85