I have 2 seats set up on single rx460
hdmi for seat1 and dvi-d -> hdmi for seat2

audio is available at startup if both monitors are on but after some time, periodic logouts on seat2 usually, turning the monitors off-on the output disappears from sound control.

I'm mostly using headsets on usb, which remain working, but it would be nice for hdmi audio to stay stable too if I want to watch some video for ex..

seat3 hdmi audio - being connected to a separate nv gt430 - is not affected

I'm wondering if anyone else has similar problem, did you manage to fix it? maybe (hoping :-)) it's a driver issue which doesn't affect nvidia carda??