some clients/devices do not support various subtitles.
if your tv does not support PGS, there is little that plex can do.
try use different subtitles like SRT and see if that works better.
plex pass users can also try on demand https://support.plex.tv/articles/subtitle-search/
I highly doubt itâs my TV thatâs the problem. I have the TV: LG OLED55B7V
Is PGS subtitles working for you or anyone else though? When using Plex app on TV?
Pgs work great for me on shield.
If you disable pgs subtitles and it doesnât transcode then you have identified and solved your problem.
If I disable PGS subtitles and play the movies without any subtitles, there is no problem playing the movies. When I turn them on the movies starts lagging heavily and sometimes audio dissapears even.
VOBSUB subtitles on my DVD movies works without any problem.
I just donât understand why there would be a problem here with PGS subtitles 
Maybe I have to look into the settings on my TV?
Thanks for answering by the way. 
I found out now that if I play the movie with low 720p resolution, itâs possible to view the movie with PGS subtitles. Very strange.
there are several different types of subtitles, not all devices are designed to use all of them (entirely up to the manufacturer/designer).
some subtitles are text, some are image based (pictures).
finally, any time that plex must transcode the audio, and any subtitles are enabled, plex will transcode the video, it does this to keep the audio/video/subtitles all in sync.
for 4k content, it takes much processing power to transcode, so normally you want to avoid transcoding 4k as much as possible (ie direct play).
if you are trying to play a 4k bluray rip, then 2 biggest problems for smart tvs and devices are HD audio (truehd/atmos) and SUBTITLES.
see above for why transcoding audio + subtitles = bad news for your server.
for a lot of 4k info, please see @ Plex, 4k, transcoding, and you
For what I understand and this applies to my setup:
PGS subtitles forces Plex to transcode the movie.
(And there are not many CPUs that are able to transcode a 4K movie.)
If I pick out the subtitle and convert to .srt, Plex will do nothing with the movie, it will be streaming (direct play) and everything will flow.
Question:
Must PGS subtitles be burned into the movie? Canât Plex display it in the same way as .srt?
As I understand it:
(Correct me if Iâm wrong)
What I have had problems with that may not be completely clear to the beginner is that the receiver, (TV or AV Receiver, etc) must pass the formats that Plex wants to broadcast. If the receiver does not meet the requirements then Plex will convert the movie or sound for the itâs requirements, if you have a server that does not manage the conversion then it will lagâŠ
This is the strength of Plex, that you can play almost anything, because Plex ensures that it works, provided the server is able/strong enough to convert.
Any update on this? Is the Plex license agreement for single-threaded PGS subtitle rendering ever going to change?
If not, then it should at the very least let it be known instead of leaving these unanswered support threads expire. It gives a very sour taste in your mouth when Plex Support just cherry picks what posts to respond to.
Nvidia shield here. No matter what type of subtitle I use (srt pgs or using built in subtitle search which I assume is srt as well) plex server starts transcoding the video. My server is powerful enough to transcode 4k but of course it looses HDR when doing so.
As far as i can tell the isseus with subs is client related. If i play planet earth 2 from my shield tv with danish subs = transcode :-(. The same occurs on the web client.
I can play the same file directry from a smb share with kodi or any other player and they have no problems with it or the subs.
If i play the same file from the native windows plex client i have no problems playing it with subtitles and no transcoding occursâŠ
So it seems to me something in the Android TV and web clients are broken.
I have seen team members state in other threads that psg subs cant be sent sidecar bla bla bla⊠but if its not possible how does the plex client for windows do it then?
I know exactly what you mean: I can play the same file with subtitles on my iPad or PC but when I try playing that same file on my LG Smart TV, it buffers insanely.
It doesnât seem to be an issue with the video codec because it streams fastly without subtitles and the codec hasnât changed.
I even tried downloading .srt and .ass alternative subtitles, nothing; the issue persists.
I am also suffering from this problem
4k Movies with external subtitle running with randomly buffering !!!
i just paid for plex pass , and i gonna canceled it .
shame it not fixed yet
I agree. Just let us know if the single-thread subtitle burning issue will ever be resolved so we can go try other products that donât have this BS. I have a shield so it doesnât affect me but my friends without them are affected, and not just for PGS, but also SRT subtitles too.
Are any of you transcoding the audio?
I noticed something really wierd.
If i have a video file where video is streamed in original quality and audio also is streamed with no changes then i can turn the subs on and off no problem. But if i play a file where the audio is transcoded (hd audio formats for me) and then turn on subtitles this somehow causes the video to switch to be transcodedâŠ
I re remuxed one of my videoes (added an AC3 stream that i can play without transcoding on my tv)
Play the file with DTS-MA audio track and no subs. Works perfect. Video shows as direct and audio transcoded.
Play the file with DTS-MA audio track and PSG subs enabled. Starts insane buffering. Both video and audio show as being transcoded
Play the file with AC3 audio track and subs disabled. Works perfect. Both audio and video show up as playing direct with no transcoding.
Play the file with AC3 audio track and subs enabled. Also plays perfectly with both audio and video showing up as playing direct with no transcoding.
So⊠For some reason the video switches to transcoding if i play a file where i am transcoding the audio and then enable subs⊠but whyâŠ
As a temporary workaround, if you go into your client > settings > advanced > subtitles and change âBurn subtitlesâ to âOnly images formatsâ it will work.
Itâs not the greatest, but with that setting everything works great for me.
I have to admit this is becoming such an annoying problem. I know that I can rule out hardware in every way shape or form. 8700K, 32GB RAM, hard line to Roku. Without subtitles, I can play any movie of any format at any quality with no problems. Turn subtitles on and anything above 1080 ( and sometimes it happens on 1080 transcodes) and it just craps the bed in many cases. I have tried using different formats of subtitles, messed with various Plex settings and same result of getting the " Your server isnât powerful enough" which is absolutely stupid. Donât get me wrong, part of what I love about Plex is getting to tinker and adjust things and part of the hobby is just the piddling around with the setup and the concept of having my own media server. There comes a point though that this should have somewhat a fix. Iâm by no means a AV guru, but I am a Network Engineer, so I know if this is giving me this kind of grief, I can only imagine what Joe User deals with. Like I said, I donât mind trying a few various things, but this for me has been the only problem that I have not been able to fix or seen that has been an existing issue for so long. Bottom line is that this issue is software, not hardware, so this has to be fixable.
Thatâs not how that works.
Plex,
HOW IS THIS STILL A PROBLEM?
This has been an issue for years. It continues to be an issue. You can hide behind the âwell, your hardware isnât good enough to support HVEC transcodingâ five generations of CPU development ago, but weâre way, way, way, way past that now. Something doesnât work the way it was intended, unless you intended for the disabled not to be able to use 4k content. You continue to add amazing new features that no oneâs asked for in partnering with external sites to serve us ads in video content none of us really cared about - but you canât seem to sort subtitles on HVEC content.
Setting my quality down to 8 Mbps 4k (also known as ânot really 4k, because we canât deal with actual 4kâ) doesnât do anything. Switching to an external subtitle source didnât do anything. What are you doing? Why are you adding new features connecting to EXTERNAL MEDIA which, unless Iâm mistaken, Plexâs original intent was to make LOCAL MEDIA available in an interface, when that local media is laughably badly implemented when subtitles are used? How is this not something that just makes you feel like total garbage, day in and day out?
I work in online media, when our content and its delivery sucks, I feel awful. We look like crap. We are jokes, at least to me. But this has been going on for years now. This is wearisome and infuriating.
iâm having the issue jens_holstschumacher.dk described. the video is transcoded when i enable SRT subtitles, only when when audio is transcoded. cpu usage goes to max and video keeps buffering. if I donât enable subtitles, and watch the video with transcoded audio, everything is fine. is this going to get fixed?
burn subtitles as only image formats doesnât do anything for my srt subs.
bump. Experiencing the same issue on a
I9-9900K
64GB 3600 DDR4 Ram
SSDâs for days
Server and 4k storage on a 1tb NVME
Hardware Acceleration enabled for when I dont use the PC (2080ti)
I know transcoding isnât an issue for my pc -
Please fix this issue - 4K movie demand with TrueSound/Atmos is getting more and more normal
Same thing here. I9 9900k, 32gb, nvme. 4k and subtitles drain the cpu and buffer every 3 seconds.
