As I have had some - similar issues with my USB port, I did some troubleshooting (internal testing tools) and submitted the ticket via self-repair portal - I couldn’t find anything specific to the usb c port since charging worked fine, so I chose the path with headphones not working via adapter which was also correct in my case.
I got an almost automatic offer to send my phone for repair. I decided to purchase a spare one and see if that helps. Will report the outcome.
For Android Auto I use a USB-C/C cable, for connection to the PC I use a USB-A/C cable, for the Flir device there is a direct connection. Charging functions still good all the time.
I am wondering why the USB preferences can not be altered.
USB contacts are designed so that when disconnecting, the data connection gets severed first, the power connection last, and vice versa when connecting.
It is entirely possible for lint or dirt to hamper a connection just enough so that a power connection is there but a data connection is not, in which case charging would work, but data connection options wouldn’t be available.
This week I ordered a new USB port. The replacement was simple and well described (take care to look for the video description for the FP5 - the description for the FP6 is really different!). All tested functions work again now.
That still leaves the question: Why can I not change the USB preferences/use/etc?