Plex 4K HDR problems

MG42Maniac · 24 Feb 2018 at 11:50

Hi All,

I am having some problems getting 4K HDR content to work properly. I have the following set up:

Plex Server: 2 x E5-2680 v2, 64GB, 30TB, Cat6
Plex Client: i5 4590, 16GB, SSD, GT1030, Cat 6 running Windows 10
AV Receiver: Onkyo TX-NR676
TV: LG OLED55B6V

I have been running 4K HDR with DTS/DD fine using XPlay on the TV. I recently bought a new AV Receiver and a GT 1030 so I could run 4K HDR with all audio.

I've tried using Plex Home Theatre and it wants to transcode down to 1080p. OpenPHT seems to play in 4K but has god awful stuttering. Have I got a setting wrong or will neither of these versions of Plex actually work with 4k HDR with HD audio?

I've got windows set to 3840x2160, YCbCr422, 12bpc, RGB and Full. This seems to trigger "HDR Mode" on the TV so I think it's set up right. HDMI Deep Colour is enabled for the input on the TV. One question about this, should it be enabled on the HDMI input that is doing the ARC as well?

Audio options within Plex are Directsound (I think) with all the audio options for "[Codec] Capability" checked. I've tried unchecking these options but it does not seem to make any difference.

I've probably missed a tiny obscure setting somewhere. Any ideas?

Thanks!

MG42Maniac · 5 Mar 2018 at 10:07

wellibob said:
Check that direct play is enabled in client playback settings. Should say "original 4k" or something very similar not like "1080p 20 mbps" Hope you get it sorted.

It's trying to transcode for Plex Home Theatre, Plex Media Player also tried to transcode.

hyperseven said:
Didn't think Plex could do HDR playback.

It doesn't look like it can.

DataVampire said:
Do not use plex for that type of playback it is awful to say the least.

Just pay a few quid and get x-play instead far far better.

I actually use plex for just 1080p content. all other stuff i use x-play.

just buy it you will thank me after

ALready using xPlay, been using it over a year, it's amazing. It will not do HD audio though. I used VLC to play a 4K HDR film and the HD audio makes such a difference. Only issue was that VLC didn't seem overly smooth during playback.

jpaul said:
he said he was using x-play but now wanted his av in the loop ?

so have you also tried mphc on your htpc ? assuming - it is your windows htpc running the plex client,
whats arc got to do with it, is your htpc not dasiy chained to Av and then tv ?

Yeah, want AV in the loop. I've tried VLC (now it supports HEVC 10bit) and it works but the playback is not as smooth as it is on Xplay, audio is much better though. I've tried PlexKodiConnect but this produces a washed out image that is stuttering. I'm wondering if I should just use plain old Kodi?

MG42Maniac · 5 Mar 2018 at 11:32

pepp77 said:
Plex can definitely do HDR, as I have played a few things in 4K HDR through the Plex app on my Sony 4K TV.

Yes, it seems that TV Apps can run Plex 4K HDR but only with DTS or DD, not the HD versions. I want 4K HDR with HD audio, for that, I need to go via my PC, however, nothing seems to be really working that well!

MG42Maniac · 5 Mar 2018 at 12:03

pepp77 said:
https://forums.plex.tv/discussion/301780/howto-4k-hdr-and-mvc-3d-in-plex-for-kodi-on-windows - might help

Awesome, that looks like it should solve my issues. I will give it a go when I get home later on. Considering 4K HDR has been around for a while there are a lot of tweaks and tinkering needed to get it working!

MG42Maniac · 5 Mar 2018 at 14:18

jpaul said:
You could also tell us what the failing media container and audio/video codec are, since maybe you need to re-mux see, my earlier post

Sure, I think this is what you're looking for:

Video Resolution 4K
Duration 1:55:49
Bitrate 91969 kbps
Width 3840
Height 2160
Aspect Ratio 1.78
Container MKV
Video Frame Rate 24p
Video Profile main 10
Duration 1:55:49
File "XXX".mkv
Size 74.41 GB
Container MKV
Has Thumbnail 1
Video Profile main 10
Codec HEVC
Bitrate 73411 kbps
Bit Depth 10
Chroma Subsampling 4:2:0
Color Primaries bt2020
Color Range tv
Color Space bt2020nc
Color Trc smpte2084
Frame Rate 23.976 fps
Height 2160
Level 5.1
Profile main 10
Ref Frames 1
TitleXXX
Width 3840
Codec HEVC
Bitrate 7607 kbps
Bit Depth 10
Chroma Subsampling 4:2:0
Color Primaries bt2020
Color Range tv
Color Space bt2020nc
Color Trc smpte2084
Frame Rate 23.976 fps
Height 1080
Level 5.1
Profile main 10
Ref Frames 1
TitleXXX
Width 1920
Codec TRUEHD
Channels 7.1
Bitrate 4607 kbps
Language English
Audio Channel Layout 7.1
Bit Depth 24
Sampling Rate 48000 Hz
TitleXXX
Codec DCA
Channels 7.1
Bitrate 1536 kbps
Language English
Audio Channel Layout 7.1
Bit Depth 24
Profile ma
Sampling Rate 48000 Hz

MG42Maniac · 6 Mar 2018 at 10:33

So I've now set up DSPlayer and all the associated things. I've fired up Dunkirk in 4K with DTS-HD, it looks and sounds incredible. However, I'm not sure if it's my OCD but I still think the picture is not as smooth as it is when using the built in XPlay app. I will take a short video tonight and upload it to Youtube, I reckon people will be able to spot any issues?