[Fataltru]

Вот, какую инфу я нашел(более подробно чем сказал Бандит).

Mercedes uses an aerial amp because there are 4 fm and 2 am aerials in the rear window.The aerial amp switchs between the different aerials to get the aerial with the best reception.
The problem is that the aerial amp don`t know,which aerial reception is good.The signal that the current used aerial has a bad reception comes from the original radio (Audio20,Audio50 or Comand) in form of a ZF-signal.Then the aerial amp changes the aerials,till the radio says o.k..This goes so fast that you don`t notice that.
The dynavin Radio is not able to send this signal out,so the aerial amp receives always from the same aerial.
I have the same problem and i bought a DIN aerial adaptor to double-fakra (Z) with pantom power (supply?) and diversity.This is usually for cars of the VW/Audi group.
I received the adaptor today and i hope that i can install it next week.Hopefully it works!
I hope that i could help you a litlle bit.