Maybe I should have added to my original post that this happens when the empeg is fully out of the sled (and in the house).

Then you are almost definitely talking about some kind of a wiring problem. Re-check all connections, plugs, and wiring runs. Even the ones you're sure are fine. Check to make sure that no wires have pulled out of their connector plugs or gotten loose.

Can you give us a more detailed wiring description?

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Tony Fabris