Artifacts on dark scenes

I’ve experienced some posterisation artifacts in dark scenes on HDR movies with infuse 6 pro.
I compared scenes using infuse, plex on my Apple 4k tv and also my htpc and those artifacts are way more visible when using infuse. For information I have a Sony xf9005.
I’ve attached some pictures to compare.
The first is when played with infuse, the second plex on Apple tv and the third with my htpc.

Thanks for help

Are the htpc and Apple TV using the same HDMI input on your tv?

No I use two differents ports.
Here is another picture of the problem.
But when I run the movie with plex on the Apple tv it’s fine, I don’t have these artifacts

Do you have the Match Content options enabled, as described here?

Yes both options are enabled

Is Plex playing it as HDR or SDR? Any transcoding going on?

As HDR. For transcoding I don’t know, I ve no idea how to check that.
Could it be a chroma error when upsampling from 4:2:0 to 4:2:2?

Possibly, yes. With the Apple TV set to 4:2:2, the video output will be 12bit. 4:2:0 is 10bit.

All commercial HDR10 videos are encoded at 4:2:0, so there is really nothing to be gained by using 4:2:2. You may try switching to 4:2:0 to see if things improve for you. Some TVs do have issues with 12bit input.

I understand but I think I can only output in 422 if I want to output at 24hz with hdmi 2.0 right?

24Hz will work when using 4:2:0 on HDMI 2.0.

I was unable to set 4:2:0 24hz in hdr so I did it in 60hz with frequency matching off but the problem remains unfortunately.