I got mine to work - Had to get an extra Metra plug do the following connections

DSP AMP Large 15pin connector, to aftermarket Metra 40pin plugged into stock radio brain in the trunk floor


DSP #4 to aftermarket metra #13
DSP #8 to #15 "
DSP #15 to #12 "
DSP small connector with white with yellow marks to Metra 9

Metra #16 to Purple with white line on EOM Harness that was originally plugged into OEM radio, but now plugged into Eonon extended harness

NOTE: I have the 40pin connector

Get your extra Metra plug here : Metra 71 9003 Reverse Wiring Harness for 2002 Up BMW 5 Series Audi Volkswagen | eBay