Xperia 1V not passing sound to hearing aids

[TheCustomer]

I'm struggling to get Xperia 1V to pass call audio and stream music to my hearing aids
(Oticon mini rite)

The phone can do this - I've had it working after a series of pairing/unpairing/repairing. But I can't say what I did to get it working other than turn it on & off several times.
I then lost the ability when I'd connected by USB-C to a different sound output, my car, which was recognised as a headset.
The phone didn't revert to the previous working audio streaming setup after I disconnected from the car.

But it still detects and automatically connects to my hearing aids, and defaults calls to Bluetooth, which I then can't hear.
I've just switched from a Google Pixel, where the sound worked faultlessly, so stock Android 14 doesn't have these issues.

Any ideas on how to fix this?

What can I do to set 

[TheGOAT]

@hehduda What did they advise you when you contacted them? Did they offer any troubleshooting steps or to send it to repair or what?

[hehduda]

I have not contacted Sony.
I received my hearing aids at the end of March/beginning of April and tried to isolate the problem; Settings of the hearing aids, the devices themselves or the phone.
When I found this thread and read @TheCustomer 's report about his contact with Sony Support, I found it pointless to contact Sony.

Note: There was a mistake in my second post: of course I meant the manual for the Xperia 1V.