Bob, I will be getting a new amp anyway as I have the older type. What is the thin white cable with brown plug for? I cant remember.

From here, I guess its this one ?

05 Antenna cable Diversity NG 1335MM 1 09/2001 61126912489

RealOEM.com * BMW E46 330Ci SINGLE PARTS F ANTENNA-DIVERSITY

Thanks by the way!