w203 TV antenna amp problem & part numbers & vin/chassis nos

[perdikoula888]

Hi, I have replaced my original antenna amp A 203 820 64 89 to accomodate the retrofitted tv tuner.
I have INITIALLY ordered from mercedes the following part number:
A 203 820 69 89
However I received the following (due to superceded number):
A 203 870 31 89
Everything works fine (tv, command, radio etc) however i lost remote central locking keyfob functionality (only infrared works close to the door handle).
I went to mercedes dealership, they diagnosed and said that the antenna amp was faulty. Thay ordered another one but the problem still remains. They suspect wrong part number or wrong supercession and they wait confirmation from the central Mercedes office (Milton Keynes) in the UK.

Do you think it is the wrong part number or it might be something else and they just made wrong diagnosis?
Has any of you retrofitted TV equipped antnna amp and what part number have you used? (MIRO, SUNMAN, STEVE etc please let me know what part number have you used for your cars).
Also does anyone have a valid w203 chassis/vin number for a factory TV equipped c-class just to verify correct part number? You prompt reply would be appreciated as need to get my car back asap. thank you.