Hi,
This is just a guess, but if you do have very tight space behind your unit (how the .... do you fit 2M of cable in there if theres not much space??), perhaps the shield of the line-cable touches the empeg sled. This will explain why its not a problem when you remove the empeg and sled from the dash ...
If this is the case, insulate the line-cables with some tape, so they don't make a ground loop when pressed against the sled.
Alternatively solder a wire to the black wire (GROUND) going in the harness to the sled (there is a threaded hole in my sled, where a screw will fit nicely with a ground wire).
Happy hunting,
Lars
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Lars
MkII 40gig 090000598