I am facing what I am calling a buffering problem when playing h265 files on the linux pc, but the same file on the win10 Plex version is fine. The local playback on Zorin is stopping every 10-12 seconds, the buffering circle appears, then plays for another few seconds, over and over. System resources show the CPU is running constantly at 80% on Zorin, 25% for the win10 while local playing AND remotely.
The hardware is obviously the same, the latest nvidia drivers are apparently installed and the 265 transcoding options are active on both systems. GFX card is GTX1050Ti.
This is a make or break issue for me. Where to start looking?
Hi there, thanks very much for your reply, hope the below is all you require.
I noticed that the Zorin plex started to playback in original resolution but after a few seconds changed to transcoding, but was showing it’s playback as “Convert to 20160p 4K (Maximum) 37.7 Mbps”, even though that is the same as the original file. Whereas the windows plex was playing original for local+webtv.app+iphone on 4G @720p, with relatively low CPU %.
There are two log files. I found that on he first try there were two transcode tasks running at the same time. These were using a combined CPU of approx 80%.
If I disable transcoding on the Zorin plex, I will immediately get the warning message “Not enough CPU for this conversion”.
Plex is failing to engage the Nvidia 1050 Ti when transcoding video, and the CPU in your server, an i7-2600, is not powerful enough to transcode 4K video by itself.
From Plex Media Server.log
Sep 13, 2025 14:39:37.059 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: testing h264_nvenc (encoder)
Sep 13, 2025 14:39:37.059 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: hardware transcoding: testing API nvenc for device 'pci:0000:01:00.0' (NVIDIA GP107 [GeForce GTX 1050 Ti])
Sep 13, 2025 14:39:37.063 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] - cu->cuInit(0) failed
Sep 13, 2025 14:39:37.063 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] - -> CUDA_ERROR_NO_DEVICE: no CUDA-capable device is detected
Sep 13, 2025 14:39:37.063 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] -
Sep 13, 2025 14:39:37.063 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: hardware transcoding: opening hw device failed - probably not supported by this system, error: Generic error in an external library
Sep 13, 2025 14:39:37.063 [132872582347576] DEBUG - [Req#7f/Transcode] Could not create hardware context for h264_nvenc
Sep 13, 2025 14:39:37.063 [132872582347576] DEBUG - [Req#7f/Transcode] MDE: Cannot direct stream video stream due to profile or setting limitations
Sep 13, 2025 14:39:37.063 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: testing hevc (decoder) with hwdevice nvdec
Sep 13, 2025 14:39:37.064 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: hardware transcoding: testing API nvdec for device 'pci:0000:01:00.0' (NVIDIA GP107 [GeForce GTX 1050 Ti])
Sep 13, 2025 14:39:37.068 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] - cu->cuInit(0) failed
Sep 13, 2025 14:39:37.068 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] - -> CUDA_ERROR_NO_DEVICE: no CUDA-capable device is detected
Sep 13, 2025 14:39:37.068 [132872582347576] ERROR - [Req#7f/Transcode] [FFMPEG] -
Sep 13, 2025 14:39:37.068 [132872582347576] DEBUG - [Req#7f/Transcode] Codecs: hardware transcoding: opening hw device failed - probably not supported by this system, error: Generic error in an external library
Sep 13, 2025 14:39:37.068 [132872582347576] DEBUG - [Req#7f/Transcode] Could not create hardware context for hevc
Double check Settings → Transcoder + Show Advanced. Make sure these are enabled/configured:
Enable HDR tone mapping
Use hardware acceleration when available
Use hardware-accelerated video encoding
Enable HEVC video Encoding (experimental) = Never. You can try changing it later, after you get hardware transcoding working.
Hardware transcoding device = the Nvidia GPU (do not leave it on auto).
Maximum simultaneous video transcode = Anything but Unlimited (due to Plex bug).
Also, make sure the Nvidia Linux drivers are installed. They are separate from the Nvidia Windows drivers.
That is pretty much all I can help with, as I’m not familiar with your setup: Zorin Linux, Plex installed via SNAP, and a Nvidia GPU. I’ve none of that on my server
Hopefully someone more familiar with your setup can assist.
Unfortunately making those changes didn’t make any diff.
I have noticed earlier that the option to change the Nvidia drivers is greyed out in the software updater > additional software window.
However, the Nvidia X server settings show the driver version is 575.64.03, which was released in Jul 2025, so assume that maybe the latest version. But I’ll check their site.
Q. Anyone advise if I run the usb installer again and choose the option to install “with latest Nvidia drivers”. Will that give me a different driver and/or allow me to choose another option in the software updater > additional software window.???
cheers CD
BTW - I have noticed that the system processes window shows the plex transcoder running at approx. 8% for a couple of minutes after closing the browser, and even though there is nothing open or playing. Could be the
I managed to get the latest driver (580) and UN-grey the additional driver options in the software-updater. Unfortunately, again made no difference. BUM!
Snap installs by default do not allow access to the Nvidia hardware and drivers. Your best option is to uninstall the snap version and download from Plex Downloads the Debian\Ubuntu .deb file. Do the Ubuntu directions.
Hi there pl-5309, that did it. the dashboard shows that the transcoder is using “HW”, haha. So thank you for your suggestion to get the gfx card usable to Plex.
The single 4K file will playback as “direct” for about 15 seconds, then go back to transcode.
So the obvious Q’s are >
why is plex using transcoding at all, when the hardware is able to playback a couple of 4K hvec 265 files at the same time.? [as shown on the windows installation.]
AND why is it ‘converting’ to the exact same specs as the original source.? = 2160p @ 37.7Mbps
Same issue, Chrome on Zorin is installed via Snap which doesn’t have access to the hardware.
You don’t really have a 4k HDR monitor and DTS-HDMA sound system connected to that PC so the Plex Client needs to do some work that the browser on Linux can’t. You should be able to install Plex for Linux from the Snap store or hit the downloads.plex.tv for a link.
Do you mean I should install the .deb package for chrome/brave? cheers
UPDATED - I see what you are getting at. It is the local playback that is not going to a 4K monitor, and the browser cannot pretend it is. But in windows it can.
I checked the playback on the AppleTv which is connected to a 4K TV. That displays a 4K, and the dashboard on the Zorin plex shows it is “direct play”.
So I have been chasing my tail, sort of. Since I really only view the movies on the AppleTv in the lounge room, browser output is irrelevent.
