Best DAC for iPhone - Volvo Car Play Connection?

Hello,

I'm attempting to improve the audio playback in my car.  I have a newer Volvo with  a Bowers & Wilkins sound system.  I'm streaming Tidal audio through my iPhone. The iPhone is connected to the Volvo Car Play via a standard lighting connector to USB cable.

The weak link in the system I believe is the iPhone DAC.  So, my question is if there is an external, portable DAC solution that would work in this situation or not?

Please let me know if you have any suggestions.  Thanks!