The problem is that I'm trying to hook my empeg up to my stock VW stero, which is all proprietary.

Do you have a wiring diagram for the stock deck? If not, get a converter plug and a master sheet from Crutchfield. Don't randomly plug in wires without knowing what they're doing.

Does the stock deck have an AUX input or a CD changer input? If the former, you're all set. If the latter, you might need a special plug and a circuit to trick the stock head into thinking the Empeg is a CD changer. (Otherwise, the head unit might refuse to switch to the CD changer input if it thinks there isn't one connected.) Be careful. If in doubt, take it to a professional who'll have the right dox and parts.

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Tony Fabris