Xbox Dolby Vision playback has wrong colours

I am using Plex on Xbox Series X. When I play back any DV Profile 5 the colours are all wrong (green tinted). I am using a LG OLED and it does say “Dolby Vision” top right.

I was under the impression from other posts on the forum that DV Profile 5 was supported?

Mode: Direct Play

Container: mkv

Video: 4K DoVi (HEVC Main 10) (Dolby Vision Profile 5 video)

DoVi: Level: 6 Profile: 5, Version: 1.0, BL 1 (compat ID: 0), EL: 0, RPU: 1

Audio: EAC3 5.1 + Atmos

Server Version#: ?
Player Version#: 5.94.1

If I use the LG app, colours are correct. So this is an issue with the Xbox version. Unfortunately due to LG’s sloppy 100mb ethernet connection / slow CPU its not good enough for larger files.

With regards to my Xbox, it has the latest console update installed. It has under Video Modes “Allow Dolby Vision”, “Dolby Vision for Gaming” all ticked.