Just change the resolution to 1080p. It should work.
No it doesnt, Sam.
Changing it to 1080p was what caused this Problem.
Now it doesnât matter what resolution i use for the GUI. 4K Movies will not play or they play like: HDR on, off, on, offâŚ
Cheers
Mario Pedro
Need to see a log at 1080p if unsolved in the next update
Cheers
OK 
Itâs a weird problem, seems like the C8 Problem thatâs been discussed a lot in this community.
After all i have a LG TV 
Take care
Mario Pedro
Hello everyone
I wanted to give an update on this matter:
I came home yesterday and did a factory reset to my TV. After that 4K HDR Files started to play again without losing the signal. Atmos also works fine from infernal Apps as well as the Vero.
There is obviously something wrong with this whole HDMI/CEC/ARC story, but i donât think itâs OSMCs fault, at least not entirely because most complains i See online are with Samsung and⌠LG TVs.
There were a lot of picture quality settings i changed, mainly HDR settings, before this issue set in. So i think it has something to with that. I donât even have the courage to mess around with them, for further picture quality improvement 
Best regards and a happy New year
Mario Pedro
1 Like