Using iPhone SatNav through car speakers - delayed audio - fixes?

[andy]

We have a Jazz 2013. Connecting the iPhone to the car using Bluetooth was pretty easy, seems to work ok for taking calls.

Using Apple Maps though the audio cuts off the start of each direction, like there is a delay in the audio being picked up.

I got a usb converter hoping that it would recognise the iPhone and run the audio though that. All it is doing though is auto playing AppleMusic every time it is plugged in.

Does anyone know a way round this, or a good fix?

Thanks