Server Version#: Version 1.26.1.5772
Player Version#: 9.1.0.32210 (794776f6)
I’ve run Plex for many years on 1080p devices. I replaced my old TV with an LG G2 and wanted to try 4K content. I’m playing from an Nvidia Shield pro SW version 9.0.2 (33.1.0.319).
Everything 4K I play shows on the Plex server as transcoding from 4K to 1080p to play, and I can definitely tell from the CPU load transcoding is occurring. Any idea what could cause this?
The Shield is running in 4K “HDR10 Ready” default display mode. I made sure the player and the Plex server have all streaming rates set to Maximum. I’ve tried playing maybe 8 different pieces of media I’ve accumulated from before I had a 4K display that has various encodings (h264, h265, etc). They all transcode for 1080p.
I even tried the WebOS Plex client on the TV, and it also transcoded 4K content to 1080p, but I don’t know how much parity that client has with other clients. I tried playing from the Plex web client on my computer as a test, and one of the 8 pieces of media did NOT transcode and DID play at 4K, but does not play that way on the Shield.
One other thing: the TV is connected to the shield via a Denon X3700h AVR. This doesn’t cause an issue for the Shield itself, which knows it’s running in true 4K. But maybe for Plex?
Why would it seem like everything gets transcoded to 1080p rather than 4K? Is there a very restricted set of codecs / media types that Plex will play in 4K? Surely there’s no way Plex could “remember” my player always used to be restricted to 1080p? Any suggestions on what I could check?
PS: The Shield 4K AI Upscaling option is set to “maximum” and I have to say does a really good job. 1080p content really looks good, I did not realize it was not actually playing a 4K stream to the display until I saw the server was transcoding.
Connecting the Shield to the TV will result in additional audio transcoding, as current LG TVs do not support passthrough for DTS audio formats.
The Denon will not cause audio transcoding problems, as it supports all the audio codecs you’ll find in current media (I’ve a Shield connected to a Denon 4300H). Also, it will passthrough the video to the TV.
The Plex Android TV app on the Shield has poor ASS subtitle support. Enabling them during playback results in video transcoding. PGS/VOBSUB/SRT subtitles should not cause video transcoding during playback.
In the Plex app on the Shield, set Passthrough = HDMI and Burn Subtitles = Automatic.
In the Shield (not Plex) audio settings, leave the audio support at Auto (default). Do not pick individual audio codecs to enable/disable.
The Plex webOS app is not as full featured as the Shield due to TV limitations.
All DTS audio formats and TrueHD will transcode as they are not supported by the TV.
Enabling PGS or VOBSUB subtitles results in a video transcode.
If the audio is transcoding, enabling any subtitle, including SRT, results in a video transcode.
Recreate the problem, then pull your server log files and upload them to the thread:
Set your Plex server for debug level logging.
Settings → Server_Name → General
Set the Plex app on the LG to log to server at the debug level.
With no other Plex activity (streaming, adding media, etc), on the Shield, without subtitles, play one of your 4K H.265 files. Let it play for 15 - 20 seconds.
Repeat using the Plex LG app and the same video.
After stopping playback, wait two minutes for the server to settle.
Pull logs (Settings → Troubleshooting) and upload to the thread.
Also, please retrieve the Plex XML Info for the video file and attach to the thread. Save the information as a text file or compress it. The forum does not support .xml attachments.
MYSTERY SOLVED! Very sorry for wasting anybody’s time.
I had Limit Remote Stream Bandwidth set to 8Mbps (1080p). I had my local LAN subnet set in the network settings. However, last year I segmented my LAN into multiple subnets with IOT and streaming devices on a separate subnet from servers and client laptops. I had not updated the local LAN subnet to include the net streaming device subnet, which the Shield and the LG TV is on. As a result Plex was treating it as a remote device and limiting the bandwidth to 8Mbps (1080p).
I changed this settings and problem solved! 4K now plays w/o transcoding on the Shield. Incidentally, this is why I could get a few things to play in 4K on the web client on my laptop, it was on the same subnet as the Plex server. Thanks to those who looked at this to help, and again very sorry for wasting anyone’s time!
