Sound quality at radio reception fluctuates

A nice evening all together from Bremen, my C4GP year 2016 torments me for about 10 months a really annoying problem. The sound quality at radio reception varies from louder to quieter or light too dark. I try to explain this. When I start the car everything is great. As soon as I start the sound gets darker, so all if I take out the heights or stuff cotton wool in my ears. After a short time or a few meters, it gets better again with normal reception. The problem is a little less in rural areas than in the city, but it still exists. In my opinion it is due to a too weak FM signal on the radio. I was 8 times in the workshop now, got 5 software updates, a Citroen action about bad reception was carried out and just today I got a new A The technician recorded these fluctuations with a test device about 2 months ago and sent a protocol to Citroen. It is said that I am the only one with this problem says Citroen and leaves me hanging. This is allegedly not possible in the city area otherwise. I have never had problems with the radio with various vehicles. A friend reports about his Peugeot 5008 about the same problem and a new antenna cable. c at Peugeot he is the “only one”. I would be interested to know if anyone in the forum still has such problems especially with such sound fluctuations. There are reports about noisy reception and jumping out stations. That’s not the case with me. In my opinion the SMEG would have to be changed, that was confirmed by the workshop master, but Citroen puts himself across. I also made a direct phone call with Citroen Köln and they wanted to get on with the technical support But there never came an answer from them. Maybe someone here knows more. Thank you Jörg from Bremen