iPhone 14 Pro- Bluetooth issues

I have an iPhone 14 pro, and the Bluetooth is driving me crazy.

The only way to describe it as to what it’s doing, is that effectively when it syncs with any of my cars stereo it doesn’t allow me to do anything else. the way it displays on my car stereos (in 3 different vehicles) is like I’m on a phone call with the phone icons up on the various screens.

whilst this is occurring I cannot use the head unit in the car to make phone calls, change to radio or the like and I cannot use any of the steering wheel controls to skip songs etc or make calls. The only function that works is the volume up, and volume down buttons on the steering wheel.

i have tried hanging up the phone on the head unit display but none of this works.

Also while it’s doing this the sound quality that is being blue toothed to the stereo is terrible and I would liken it to the music quality you experience while on hold on a phone call.

initially I thought this was an issue with Siri as I was experiencing it when I tried to summon Siri, my solutions to fix have been to deactivate Siri, however it still randomly happens all the time.

other remedies I have tried are 1) phone updates

2) a complete factory reset of the phone wiping all data and settings

3) deactivated Siri as it was more prominent when she was being used by my phone.

none of the above have rectified the issue. Has anyone else had a similar problem and if so how is it fixed?

Or simply do I have a defective phone that I need to claim a warranty on?