Have a go at this one...

I've got my main Empeg in the truck I drive everyday to work and back and it's hooked up as an AUX Mp3 player for my Alpine headunit (using the headunit's AUX input). Since day one, I've always had to have the Empeg turned off while listening to the radio because of massive interferance/static that happens if the Empeg is on. I've always figured I had a ground loop issue and I've just learned to live with it. Turn the Empeg off when I listen to the radio, turn the Empeg on when I want to listen to Mp3's, easy. The noise doesn't effect Empeg playback or CD's, but it completely wipes out AM and gives a barely noticeable FM static (remember, this is only with the Empeg turned on). Here's the kicker... the other day I pulled a player from one of my other cars and slid it into the Empeg sled in my truck, within seconds I realized that the Empeg was ON and there was no static in my AM signal? just to check that I wasn't crazy, I turned the Empeg off to see if the AM signal changed, nothing! I went straight home and grabbed the player from my wife's car and slid it into my truck and still no radio interferance! So what gives? It's obviously that specific player that is causing the issue but where do I start? Is there something I've overlooked in the settings that could be causing it? Any ideas?

Ok... I started messing with this thing last night and found that for some reason, on my main Empeg player, the Dimmer is causing this static when listening to AM if the Empeg is on. With the Empeg off, no static. With the Empeg on but the Dimmer turned down below 50%, no static. This player is not hooked directly to anything except my Alpine headunit. Not to my antenna, not the amps, not headlights, nothing... So what's going on? Anyone who understands the internal wiring of the Empeg that can enlighten me on this. It's only this particular player that does it, none of my others have this problem.

Do you have an original empeg lens on the problematic unit or a DarkStorm lens?

Standard original Empeg Blue lens, why?

This isn't one of those "Have you checked the air in your tires" questions, is it?

The DarkStorm lenses aren't shielded, and since this seems to have something to do with the display and RF interference, that seemed a likely culprit (not that anyone has reported this before, to my knowledge). But you've got a shielded one, so that's definitely not it.

I'd contact support. It sounds to me like something internal to the unit has failed to be grounded properly, but I'm not an EE, so I could be wrong. Regardless, it sounds like a fault that will require a physical solution.