This can be very annoying if you listen to the radio a lot. But luckily there is a very easy solution for this. We at Carpar always use antenna amplifiers if a customer has a radio installed with us. Unfortunately it sometimes happens that the signal is weak, this sometimes has to do with the car having a small antenna, or because the car's antennas have been specially developed for the original radio.
This has nothing to do with the quality of the radio, we have experimented with this by mounting the same radio in 2 different car models, one car had very good reception, and the other less, but this can always be solved with an antenna amplifier. Therefore, use an antenna amplifier and try to turn off the AF option via the Radio menu.
You can search for an antenna amplifier through our webshop, there are a few versions, they are all equally good, please check the connection when you order it.