connecting phone to car mutes car radio

I have an iPhone 13 pro and a 2016 Seat Ibiza. Since the 15.6.1 update I’ve had a problem with the connection between the car and the phone. When the phone is connected to the car via Bluetooth the car DAB radio goes silent. I’m not trying to play music through the phone, just continue to listen to the radio and allow the navigation on the phone to interrupt the radio to provide guidance or calls to come through the car. It worked fine from the day I bought the car from new until I did this last update.