No sound through dock connector in car

Hi I have a iPhone 12 with iOS 14.4 and it has never worked with my car USB.

USB connect to car, and no audio plays. 

Ever since the latest update, I can no longer play music through my usb. The display will show which song is currently playing but there is no audio no matter what I do. Is there going to be a new update for this?

my car touch screen is designed to be used with iPhone and it had always worked with my iPhone X my friends iPhone XR and my iPod touch but never with a 12 or the new SE!

it is a basic function why would you mess with it!! I have tried all the different fixes you recommend but they have not worked!!! And I cannot update the car firmware because I can’t find it and Peugeot don’t want to help.

why mess with what works unless this is just apples sneaky way to get everybody to spend more money on CarPlay!

Oh and the blue tooth is sketchy too, but it works just not as great as it is supposed to!