Fire TV 4k Max Blank screen playing **Some** DV (provile 7.06) movies while others play fine

[spinmaster]

Hi All

Issue:
Some 4k Dolby Vision (Profile 7.06) Remux movies playing through the Plex App on the Fire TV 4k Max show a blank screen. The sound plays fine.

Setup:

• Fire TV 4k MAX (directly plugged in to HDMI 1 and using external power). NVidia Shield is on order!

• V LG C9

• Soundbar Sonos Arc

• WIFI: dedicated Unifi Nano HD (300+ mbps) 5G only (2.4 turned off)

• Plex Server running on unraid.

• All Movies are backed up using MakeMKV thus using a mkv container

The following movies play fine with Dolby Vision triggered:
Dune, The Batman, The Matrix, 2001: A Space Odyssey (and more all play fine)
The MediaInfo tool reports:
Dolby Vision, Version 1.0, dvhe.07.06, BL+EL+RPU, Blu-ray compatible / SMPTE ST 2094 App 4, Version 1, HDR10+ Profile B compatible
or similar (but always dvhe.07.06, BL+EL+RPU)

The following movies all trigger Dolby Vision but display a blank screen (sound plays).
No Time To Die, Top Gun, Top Gun Maveric, 1917, Jaws, Back to the Future (1-III)...+ others
Along with the blank picture, none of the overlays (play pause etc., fire tv developer menu tools) are displayed.
Again MediaInfo tool reports:
Dolby Vision, Version 1.0, dvhe.07.06, BL+EL+RPU, Blu-ray compatible / SMPTE ST 2094 App 4, Version 1, HDR10+ Profile B compatible.

What I've tried:
- Re-running MakeMKV on the mkv files. Same result
- Remuxing to mp4 and ts containers. DV is not triggered.
- Comparing the working mkv files with the none working files using MkvtoolNix (info section). Nothing jumps out as different.
- Used the FireTV Developer Menu to dump the output of the overlay service (since it's a blank screen) and then compared the results. Again nothing obviously different.
- Checked the TV's Service menu overlay, cross referencing with the DV from Disney+. All display sYCC601 for the color space. (I have read elsewhere that most of the other info in the Service Info screen is incorrect rubbish)
- Tried Jellyfin, using both the exoplayer and the libvlc players. Same result, blank screen, with audio playing.
All I can think is that maybe the files have a bad DV BL or EL layer. Maybe the luminance levels are all zero? Note, the "Mastering display luminance" and similar metadata looks ok.
Anybody got any thoughts on what might be going on, or what I can do to investigate further? Maybe it's just a FireTV player bug that will get ironed out. Since DV Profile 7.06 is not officially supported.

Final Notes:
I don't want to remux to other DV profiles (5 or
I have a Nvidia Shield 2019 on order, but thanks to some postage strikes, it looks like that is going to take a few weeks to arrive .

TIA

[quietvoid]

Known issue of the device. It shows a blank screen for FEL titles.
The problem used to be fixed on 4K Max, but an update reintroduced it and FEL files don't work anymore.

[bitspyer]

Hm..
I also use a 4k Max and 'til now no Problems with the Files and Dolby Profile 7.
My Setup is

LG CX9
Denon AVX 1400 (where the Stick is plugged).
I use KODI for Playback the DV Content.

[speeddemon]

I think the problem here is actually with HDR10+ files. I'm running into the Blank/Black Screen Issue even on files with the following HDR Format on my Fire TV 4K Max:
"Dolby Vision, Version 1.0, dvhe.08.06, BL+RPU, HDR10 compatible / SMPTE ST 2094 App 4, Version 1, HDR10+ Profile B compatible"

[quietvoid]

I think the problem here is actually with HDR10+ files. I'm running into the Blank/Black Screen Issue even on files with the following HDR Format on my Fire TV 4K Max:
"Dolby Vision, Version 1.0, dvhe.08.06, BL+RPU, HDR10 compatible / SMPTE ST 2094 App 4, Version 1, HDR10+ Profile B compatible"

In fact, it is with both HDR10+ and profile 7 FEL files!
Profile 7 FEL only: blank screen!
HDR10+ AND Dolby Vision: blank screen!