If you edit the hevc mkv file with mkvpropedit and delete color elements like in the above post then you can Direct Play the mkv file to the Roku Ultra and it displays perfectly.
That assumes the audio is not multi-channel AAC audio, which is popular among various release groups on the internet, etc.
In the case of multi-channel AAC audio, the Plex Server will transcode the audio to AC3 to prevent known Roku playback issues with multichannel AAC audio, resulting in the plex server transcoding the HEVC/AAC into HEVC/AC3 in a temporary MKV container. This temporary transcode will introduce the known color issues to MP4 and MKV files where only the audio has been transcoded to work around known multichannel AAC audio problems with Rokus.
All of this is well documented earlier in this thread, from my troubleshooting of this issue, going back to December of 2020.
Inotherwords, if your file has multi-channel AAC audio, removing the container color elements of an MKV container will not work around this issue.
2 Likes
Here I am playing a multichannel AAC HEVC video in Direct Play, no transcoding being done. If any audio transcoding is being done its the Roku thats doing it. Before I removed the color elements the video was dark, now its brighter, as it should be.
You are misunderstanding the issue and why the color issue applies even to HEVC files in MP4 containers. The reason why direct play multichannel AAC audio is an issue was previously mentioned in this thread. Roku Ultra 2020, aka 4800x, direct play, colors distorted when playing back HEVC, 1080p content on 1080p screen. Applies to both 8-bit and 10-bit packaging of 8-bit content - #25 by boblinthewild
Roku has a known issue with multichannel AAC audio which causes Rokus to play the audio back as dual-channel. To work around this issue the plex server converts the multichannel AAC audio to AC3 and outputs the multichannel audio in a new MKV container that contains the color elements, introducing the HEVC/distorted color issue.
Yes, you can âforceâ the Roku client to direct play AAC audio, but it will output the audio as dual-channel. Dual-channel audio is fine if you plan on playing the audio back on your TV, but if you have a surround sound system, it will completely destroy the surround sound effect.
No one is debating whether it is possible to force the plex client to direct play AAC audio. The question is do you want to convert multichannel audio to dual-channel audio and have that dual-channel audio sent to your surround sound system? At that point, are you not better off forcing the client to transcode everything, so that the surround sound works properly? Why would my brother want a dual-channel down-conversion sent to his 9.1 channel Atmos home theatre?
So youâre saying that with HEVC video and AAC audio displayed on a 1080P TV thereâs NO way to get AAC multi channel audio and correct video on the Roku Ultra player. Iâll either get screwed up video and AC3 5.1 audio (Direct Stream & transcoded audio) or great video and 2.0 audio (Direct Play). Why cant we get Roku to fix their firmware?
Heckuva good question! And one to which Roku seems to have no answer. Iâve seen posts about the Plex dev focused on Roku engaging with them, but thereâs been radio silence for months.
Bump, no movement afaict. My Roku updated to version 11 and still have the same problem
Going out on a limb and tagging @ljunkie on this. Any encouraging signs coming from the Roku folks? Or is this likely related to the hardware and thereâs little hope of a fix until the next hardware generation is released?
From a recent post on the Roku forum thread about this issue, it appears that at least one additional newer Roku device, specifically the Roku Express 4K+, which supports Dolby Vision upscaling, has this issue, besides the well-document issues with the 4800x.
Itâs strange, that this issue has persisted for so long, and has not been resolved with a Roku firmware update when the trigger for the issue is well known and easy to test/verify.
1 Like
Itâs starting to feel like it isnât fixable in the firmware.
I have read this entire thread and the entire thread over on Rokuâs site. I have a Roku Streaming Stick 4k+ (3821R) and I have the red tint issue on HEVC files.
What I discovered was that ALL of my HEVC files that did not have color space information played with a heavy red tint. I have several HEVC files that I encoded myself with handbrake and ALL of them have BT.709 for the color space and ALL of them play back perfectly.
So my fix was to use mkvpropedit to add the color space information, not remove it.
mkvpropedit <file path> --edit track:v1 --set colour-matrix-coefficients=1 --set colour-transfer-characteristics=1 --set colour-primaries=1
3 Likes
This thread and the thread on the Roku forums have been specifically about the Roku 4800x model (aka Roku Ultra 2020 release). You are describing an issue with the 3821R (Roku Streaming Stick 4k+ 2021) which was released almost a full year after the 4800x and likely contains different hardware than the 4800x.
Without examples to compare against, itâs impossible to tell if the difference in your experience is because of the change in hardware or something else.
The fact that your post is only the second report on either thread about the 3821R, in regards to the âalways-onâ Dolby Vision, HEVC issue, leads me to speculate that likely some hardware change did occur, which may explain the difference in your experience versus those of us with the 4800x model.
In past posts, I shared prior examples of what did and what did not activate the âalways-onâ Dolby Vision issue with MKV files. If you have a âsolutionâ for the 3821R please share samples so we can properly compare them against the 4800x.
Handbrake MKV/HEVC example that played back perfectly for me with the 4800x:
https://mega.nz/file/ELo1GA7Z#ymwHUOmvN3rD4qIhN3U0wLhhND759YijuDW9XxafBRE
Same video/audio with the file container remade using FFMPEG, resulting in the âalways-onâ Dolby Vision upscaler issue with the 4800x:
https://mega.nz/file/9ax0lJAZ#AcTbb0Xo5l9OhTYRJLoUH2T0bp1vN5EBGhQmvG4Nhv4
1 Like
Here is what the colors look likeâŠ
I will try the video files you posted later.
I am not trying to hijack this thread, I posted in case others have a similar issue.
2 Likes
I am sorry if I came off with a rough tone in my prior post, not my intent, at all. My attempts at brevity sometimes can give off the wrong tone.
I fully appreciate the additional information about the 3821R, itâs hard to compare one model against another without examples of what does/does not cause the issue on the 3821R Roku.
I am sure it would also help ljunkie, the other Plex staff, and those in this thread, who have tried to work on this issue, if they have examples videos to show the Roku staff, when demonstrating the issue.
Feel free to modify/use the kitten video I posted earlier if you need a non-copyright video to share for creating an example video. My wife shot it and absolutely does not care what itâs used for.
1 Like
I am sorry if I came off with a rough tone in my prior post, not my intent, at all. My attempts at brevity sometimes can give off the wrong tone.
No worries at all!
I tried both of your videos and they both direct play with both audio and video and neither video displays any issues with color.
So it looks like the 3821R has a different issue.
I have a new Roku Ultra LT, recently updated.
I seem to be seeing two different problems conflated. One is an issue that triggers the Roku to treat the file as HDR, resulting in contrast and color distortion. The other is an issue where some HEVC files are simply oversaturated, as if Roku is applying bt2020 to a bt720 picture.
My Roku has both issues. Some files require me to manually turn off HDR in the TV (Sony Bravia x800h). Others require me to reduce the saturation from 50 to 30.
Adding my voice to the hope that Roku fixes both issues. I used to have a Premiere. Dropped it because its wifi was weak. The Ultra LT has enough wifi power to handle most 4k but these color issues are maddening.
Please, Roku, fix these.
I literally just started seeing this problem (oversaturated colors on all HEVC files) on the current model Roku stick, too. It was working great until recently, so Iâm not sure which update (from Roku or Plex) caused it.
@Cafe_Diem @chroma601_gmail_com,
This thread is specifically about the âalways on Dolby Vision upscalerâ that occurs with the 4800x aka, Roku Ultra 2020, when watching SDR, HEVC video, which occurs even if a person is only using a 1080p television set. This is an old issue, dating back to at least December of 2020.
No other issues are applicable to this thread. @Cafe_Diem, If you are experiencing an oversaturation issue due to a recent Roku update, you are describing a different problem from what this thread is about and I would suggest starting a different thread for that issue. The issue described in this thread has existed with the 4800x since at least December 2020, with no change.
@chroma601_gmail_com, With the 4800x we know that color info in the container of MKVs specifically causes the issue. As others have stated in this thread, the issue is likely an unrepairable hardware issue.
If this test file does not activate the âalways on Dolby Vision Upscalerâ issue when direct played to the Roku, you have a different issue than what this thread is about:
https://mega.nz/file/9ax0lJAZ#AcTbb0Xo5l9OhTYRJLoUH2T0bp1vN5EBGhQmvG4Nhv4
This version of the same video does not have the color info in the MKV container itself and thus does not trigger the known issue:
https://mega.nz/file/ELo1GA7Z#ymwHUOmvN3rD4qIhN3U0wLhhND759YijuDW9XxafBRE
If both of those videos playback the same when direct played on your television, you are experiencing different issues than what this thread is about.
Posting to keep the thread open.
That being said, Roku did a âsilentâ Roku Ultra upgrade release in 2022 with the Roku Ultra 4802 with a new remote.
I am curious if the 4802 contains a hardware fix for the problems described in this thread with the Roku Ultra 4800. I have enough Rokus at this point that itâs hard for me to justify buying another Roku for one test at this point.
Thanks for this thread, it helped me figure out a related issue I have/had with my Roku 3820RW (The new-ish Streaming Stick 4K) which is currently at OS 11.0.0 build 4193-CU.
Iâm not trying to hijack the thread (sorry if it seems that way), just trying to provide helpful info for folks with the same device that come across this informative thread.
My issue is over saturated video playback when associated with HEVC 265 content as well. After hours of (super annoying!) testing/transcoding/jacking around I finally found for my device that it seems to NOT be related to the fact that the HEVC content was 10-bit (which I really thought it was). It turns out to totally be the container, and any reason for plex to transcode, as it transcodes into an .mkv container. This is same/similar to what was outlined in this thread already.
For my âbadâ file, the original file container is .mkv with HEVC 10 bit and EAC3 audio. Playing this natively results in the oversaturated video that looks essentially unwatchable on my SDR 1080p TV. If I transcode and add another audio stream with AAC stereo downmix but keep the .mkv container with 10bit HEVC video, I still continue to get this unwatchable video stream. HOWEVER! If, I transcode adding that additional AAC stereo downmix audio stream (still copying the 10 bit HEVC video) into a .mp4 file, the playback is excellent and just as expected.
PMS Version that I am using that works for this: 1.28.2.6151 on Windows 10
Windows FFMPEG transcode command (which may require augmentation based on what source stream mappings you may have):
ffmpeg -i orig.mkv -map 0:0 -map 0:1 -map 0:1 -c:v copy -c:a:0 aac -ac 2 -c:a:1 copy fixed.mp4
Of course, if you force a video transcode in plex (which it will convert to h264), then all of this is moot as already noted in the thread, and playback is just fine at the expense of added server-side processing. I wanted to provide an idea for folks who wanted to keep their HEVC content (better/cleaner compression with lower streaming bandwidth requirements) with minimum mods to the source so once/if this issue is fixed, your library will continue to âjust workâ.
This is a real pain that we have to transcode anything, this .mkv container issue is really annoying! Roku/Plex FIX THIS PLEASE - good grief!
