I have a Theatre + LG G2 65” on motorised wall bracket (trading in for a G3 65” coming 30th May) with latest AppleTV 2022 unit (did have a 2017 device before when the Theatre first arrived last October and my comments the same) Vision works … I have the ATV going into the Theatre, so I can use the PUC.  I also have a Sky Q going into the Theatre, Dolby Vision works with PUC. Bang Olufsen Manchester did need to change all my HDMI cables despite the cable stating HDMI 2.0 and worked when they installed on previous Eclipse but the Sky Q would not get 10 bit and the ATV did not offer 4:4:4, after a HDMI cable swap (again 2.0 from same manufacturer), now all working. Additionally I have a Panasonic UB820 going into the TV in HDMI 4 and Vision works. I suggest trying a different HDMI socket on the LG first, and 2nd try a new HDMI cable.  Also recommend everything going into the Theatre so you can use the BeoRemote One with PUC. I cannot get the BeoRemote to use HDMI CEC for anything direct into the LG.  If you have a Theatre seems a shame to me in my opinion to have to use other remotes.

Thanks Simon. I too have a motorised bracket :)  I believe the installer may have mistakenly plugged into the AppleTV into the LG instead of the Theatre.  They installed a HDR Balun kit to send video to the screen from my rack which is on the other side of the room. I switched to another HDMI port but no luck. Still not getting DolbyVision thru the AppleTV.  The AppleTV I have is the A2169 which supports HDMI 2.1 upto 4k60 HDR10 and Dolby Vision. Do you think this is a cable issue as the AppleTV should give DolbyVision directly to the TV if connected directly shouldn't it?  

It seems you may have the same issue I did resolved with a cable swap.  Makes no sense but it solved for me… seems the Theatre and LG and ATV are sensitive to some HDMIs. I still get the occasional digital copy message on Disney Plus app on the ATV but a quick restart clears that. At the same time, ask the installers to run a spare hdmi as well for future proofing, at least it is fed through the bracket in case you buy another device.  I also have a spare PUC lead run through as they are known to fail.  Both spare leads are hidden behind the port cover at the Theatre end and in my device cabinet at the other end.

Sounds like you are routing some of your video sources through a matrix to the Theatre?  If so, I do the same with my Sky Q, though thats the only source routed that way. If your ATV 4K is passing through the matrix to the LG / theatre, then you need to make sure your matrix can pass through Dolby Vision.   Mine does not, so my ATV 4K doesn't go through the matrix and is connected directly to the Theatre without issues. If you matrix does support DV, make sure that that the matrix settings for that output (that carries the ATV) is set to an EDID profile that allows DV (i.e full UHD). Not sure what your pre-theatre television was, but it may be that just that the matrix output settings need to be toggled to full UHD.  Then the ATV and Theatre/Lg will recognise the whole chain as full UHD capable.  

Thanks SandyB, for clarity on your system.   I am unsure about barbar, but all of my devices are straight into the Theatre using HDMI 1 & 2 (Sky Q and Apple TV A2843 - 2022 version with Ethernet) and 3 for the eARC using supplied B&O HDMI.  On the LG, only using HDMI 3 for the eARC and 4 for the Panasonic UB820 UHD Blu-ray.  No matrix for me.  Everything can play highest definition ie DV and on the Sky 10 bit HDR HLG.  Just played around with the HDMIs and it does not matter whether the Apple TV is connected into the Theatre or direct into the LG I get DV and 4:4:4.  Also swapped the Apple TV box for my old 2017 device and same can get DV whether connected into the Theatre or LG.  PS on latest 2.5.3 (141) Theatre software. Edit… I missed you are sending from the other side of the room via HDR Balun, SandyB is on the money, probably not cables but the HDMI extender and it’s setting.

Hi Simon and Sandy, thank you so much for your help.  I worked with a recommended official installer of a store which sold me the system.  Given the installation of an electric lift and custom panel for the sound theatre it was an extensive install.  They wired the HDMI cable directly from the appletv into the LG.  It's barely been six months and they are suggesting I purchase a service agreement to come and trouble shoot. This is pretty annoying to say the least...  

you referred earlier to an HDmI balun - which suggests you have a matrix video distributor in you rack? Is that not correct? This should be easy to sort out, but its a bit tricky w/o knowing exactly your setup

Hi Sandy, "HDR Balun kit to send video to screen from rack over CAT6" is what has been installed by the "Certified B&O Installation Partner". I could take the rack out to find out exactly what has been used. I had another person earlier install a Neo Matrix 4x4 Pro which ends in other rooms in the house.  I don't really use this much though but it's on the rack.  

This means that the extender kit is used for something else…..but not the ATV, right??? It is unbelievable that a “Certified B&O Installation Partner“ would not adjust an installation, that has been done less than 6 month ago for free…. ….and instead demands a service agreement before doing the job. Also a certified B&O partner should prioritize the direct connection to the Theatre and the use of PUC for controlling. MM