Solving playback issues

[2ka]

When you turn on the subtitles, the Plex server transcodes the video from UHD HEVC to HD using the H.265 encoder.  The red saturation problem only happens with HEVC. 

The red problem goes away when you turn on substitles, but .you lose UHD.

Same thing happens, by the way, if you reduce the playback bandwidth.  When Plex server transcodes the video for lower bandwidth (and lower resolution), the red problem goes away.

[Hardworkinguy]

I'm also experiencing this issue while playing Plex video. I just upgraded to the Roku 4K and I have to say this is frustrating since my previous Roku did not do this.

[chroma601]

Hardworking Guy, the only workaround I have is to manually change my TV to bt709 when you get "the red problem". On my Bravia, it's under a menu called Video Signal in the picture adjustment hierarchy. It's usually on Auto, but Roku is assuming all HEVC is bt2020 color space so it's displaying the color incorrectly. Hope you can find the menu on whatever TV you have. Let us know.

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@Hardworkinguy wrote:

I'm also experiencing this issue while playing Plex video. I just upgraded to the Roku 4K and I have to say this is frustrating since my previous Roku did not do this.

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[Awponder]

Any update on this issue? I just noticed this on my ultra lt this evening.

[Awponder]

This is a 4k non HDR file. Encoded in HEVC 10bit. Look at the over saturation. Fix this Roku.

[chroma601]

Roku isn't telling your television the proper color space. In the video signal menu manually select bt709 for the workaround.

[Awponder]

and pray tell where this video signal option is? I do not have one.

[Awponder]

I shouldn't have to specify things for each video I am playing. Roku should fix this and then push the update to the client.

[Awponder]

I even changed the mkv container to mp4 using ffmpeg to see if that would make a diff and it did not.

[Awponder]

Playing a file that is 4k size, HEVC and 8bit not 10 bit works fine in the mp4 container. Going to try this in mkv container to narrow it down to the file being 4k 10bit being the issue.