Ok, I'll finally break down and ask for help. I have some fairly serious alternator noise on my installation, but it's fairly unusual.

1st the setup: 94 VW Golf.
Power cables for amp run down the driver side, all audio cables run down the passenger side.
The line out cables from the Empeg are wrapped in tape, so no grounding there. (Duck tape is insulating, right?).
The Sony Xplod amp is grounded only through the grounding cable.
The included grounding RCA cables are grounded to the grounding terminal on the amp.

Now the symptoms: The alternator noise changes in volume seemingly randomly. Some days it is almost non-existant, some days it is quite loud. The line noise is the same on all four channels. The noise only exists when the empeg is running or paused.

Some observations: I don't think that the empeg's power in is running next to the line outs, but it's hard to tell in the cramped confines behind the Empeg what's going on exactly. I'm also not sure if the Empeg chassis itself is grounded, and I'm not sure if it matters. I also don't know if the noise exists when the Empeg and it's sleeve are removed from the DIN slot, i.e. not installed.

Any help or suggestions would be appreciated.

Sheetzam S/N 73, 10gig, blue

Installed the Empeg (Emma as Schofiel calls it) in a BMW, yesterday, and we had quite some difficulty killing a high-pitched interference; like a soft whistling. If that is the 'whining' that you mention, you may want to try connecting the floating ground terminals to the empeg sled. It completely eliminated the problem. Connecting the floating grounds with the Amp's earth didn't make any difference at all.

With the whining removed, Emma sounds great playing MP3s. Radio sound (and reception / features / etc.) is poor. If the antenna amplifier and better software bring it to half the MP3 quality, I'll be really happy.

Henno