Hi, I'm pretty new to the empeg world and I've got a problem. I've checked through the posts and can't find anything exactly like this. Here goes...
Playing MP3s works great. Beautiful. When I switch to aux mode I get a nasty alternator whine and the input music (from any source, I've tried a few) is all garbled... sounds distorted as if amplified too much. The problem isn't in any of the wiring I did, or the devices I'm using for input. I tried a friends empeg in my car - worked perfect. So the problem lies within my empeg itself. It used to work fine, but hardly used it. When you have a thousand songs to choose from, a 12 track CD just doesn't cut it. One day I bought a new CD, went to try it out and... garbage. At first I didn't notice the alternator whine, but I paused the CD and there it was. Sounds like it might be an internal ground loop type problem. Anyway, I was wondering if anyone's heard of anything like this before?

Have you tried your empeg in your friends car ? just to narrow down the field a wee bit

Would have, but his install is very tight... no way to get at the inputs. And, I think the input is muted until it detects a signal.

Well. It's not specifically the same as your problem but it's sort of similar.

I tried plugging my laptop into the aux input of the empeg once and I had terrible ground loop problems. There was a really nasty hum when ever the laptop was plugged into the mains. It did stop once I used battery power.

In the end I just plugged the laptop directly into the amp.

- Trevor

Someone else complained about a similar problem with their Aux input, and I seem to recall that it was something faulty with the player itself (as you already surmised by trying a friend's empeg in the same sled). So you should contact support using the method described here.

That's kind of what I was afraid of. Thanks for the help.

If I want to use my Discman on the Aux port of my empeg I have to use one of the grounding cables developed for the Mk1 so that I get a nice clean signal. This cable just grounds the outer shells of the RCA connectors - well actually it has an extra cable connected to the shells that you have to tie to ground somewhere. Try pulling your RCA connectors apart slightly and grounding the outer shells and see if that helps

If I want to use my Discman on the Aux port of my empeg I have to use one of the grounding cables developed for the Mk1 so that I get a nice clean signal. This cable just grounds the outer shells of the RCA connectors

I would have said the same thing, except he said that he tried a friend's empeg in the same slot and didn't have the problem.