I did order a copy but comes next week. My setup is x800 with Yamaha 2060. I did notice some 4K titles default to wrong sound format. But on Sony remote you can push “audio” button on remote to flip thru all the formats on the fly.
Sony must be set to auto.
I know there was a thread several months ago with
@Danzilla31 with his install of x700 with his Denon 4400 but I don’t recall if he had any special setting at the AVR.