I've been thinking about the hissing problem on my 98 e320 (please see this thread: Constant hissing noises from my new sony head unit :( ) and it just occurred to me that my car might have a separate factory amp somewhere. If so, is there a way to wire my sony unit directly to the factory amp to get cleaner sound? I remember doing this exact same thing on my dad's 90 560sel (the rear amps blew so i just installed a new jvc radio with the 4 spear wires going into the amp's wire socket) The result was perfect sound. No hissing whatsoever. If the e320 has a similar setup, can somebody point out the exact location of the amp, and also what kind of wire going in and out of the amp?

Much Appreciated!

Mars