Server Version#: 1.41.5.9626-72009626
Player Version#: 4.159.0
In recent weeks, I have experienced playback issues in the Plex app on my Samsung TV. I have not encountered this issue before, and I have been playing MP4 videos from my Synology NAS server through the Plex app on my TV for nearly ten years.
Playback freezes and buffers, and then I’m shown a screen saying that an unexpected error has occurred. When I resume watching, the buffering might recur within minutes.
Having searched for answers as to why this has happened, I’ve checked and can verify that these settings are in place:
- In the Plex Server Settings, the Transcoder is set to “Use hardware acceleration when available”
- In my Samsung TV’s Plex app settings, “Allow Direct Play” and “Allow Direct Stream” are enabled, and Local Quality is set to “Original”
I was (and always have been) using WiFi to connect to my NAS server, but as of today, I’ve connected the TV directly to the router with a wired connection, using a Cat6 LAN network cable. The buffering is still happening.
I’ve not changed anything in the way I create the MP4s that I watch. Nothing has changed that can explain the buffering.
I’d be grateful for any advice on what I can do to resolve this. If you need any more information, please let me know!
Monitor playback via Plex Dashboard → Now Playing + Expanded View.
Is the video or audio transcoding?
Is the stream Local, Remote, or Indirect?
Attach a screenshot if possible.
Thanks for getting back to me so quickly!
The streaming is local, and it looks like the video is transcoding.
I’m not sure why it’s doing that. As I say, I’ve been creating my MP4s in the same way for years, and this buffering has only recently started happening.
Thanks for the screenshot.
Two things to investigate:
First, 62 Mbps for a 720p video. Something is definitely off.
Second, Plex is not using hardware accelerated transcoding.
Please do the following:
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Ensure Plex Media Server is configured for debug, not verbose, server logs.
Settings → server_name → General + Show Advanced.
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In Settings → Transcoder + Show Advanced, check these settings:
- Enabled: Use hardware acceleration when available
- Enabled: Use hardware-accelerated video encoding
- Hardware Transcoding device = the Intel graphics (not Auto)
- Enable HEVC video encoding = Never ← not available on all Synology NAS.
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Stop Plex Media Server. Wait one minute.
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Start Plex Media Server. Wait three minutes for it to fully log the startup sequence.
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Play the problematic video for 20 - 30 seconds, then stop playback.
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Download the server log files (Settings → Troubleshooting) and upload the entire zip file to the thread.
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Also upload the Plex XML Info for the video. Save the info as a .txt file. The forum does not allow .xml uploads.
I had this too on the Samsung Plex app. Gave up the whole thing for a Sheild.
Thanks for those instructions. Please find attached the server log and XML info.
Just to note regarding the Transcoder, hardware acceleration when available and hardware-accelerated video encoding were both enabled. However, Auto was the only option under Hardware Transcoding device, and Enable HEVC video encoding was not available as an option.
83540.txt (4.5 KB)
Plex Media Server Logs_2026-03-30_22-03-58.zip (3.9 MB)
Thanks for your help with this.
That means Plex cannot see the iGPU, which is why hardware transcoding is not working.
Which model NAS?
Which version of DSM?
(Replying via phone. Haven’t looked at logs yet)
Mar 30, 2026 21:58:58.601 [140387154578232] INFO - Plex Media Server v1.41.5.9626-9ba082670 - Synology DS1621+ x86_64 - build: linux-x86_64 synology-dsm72 - GMT 00:00
Mar 30, 2026 21:58:58.601 [140387154578232] INFO - Linux version: DSM 7.2.2.72806-8, language: en-US
Mar 30, 2026 21:58:58.601 [140387154578232] INFO - Processor: 8-core AMD Ryzen Embedded V1500B
The DS1621 has an AMD Ryzen v1500B CPU. It has no GPU and is incapable of hardware accelerated transcoding.
I’m surprised the option to enable hardware transcoding was even visible.
Mar 30, 2026 21:58:59.132 [140387149785912] DEBUG - [GPU] Cuda library was not found on the system
Mar 30, 2026 22:02:32.224 [140387084737336] ERROR - [Req#314/Transcode] [FFMPEG] - Cannot load libcuda.so.1
Mar 30, 2026 22:02:32.224 [140387084737336] ERROR - [Req#314/Transcode] [FFMPEG] - Could not dynamically load CUDA
Plex is trying, and failing, to load Nvidia drivers.
Have you installed a Nvidia GPU and/or drivers in the NAS?
I haven’t installed a Nvidia GPU or driver – might that be the solution?
My technical skills as regards servers are pretty low. This is my second Synology NAS, and in both cases, I’ve not done any configuration or added anything to them beyond the Plex Media Server. My main NAS use cases are file storage and media hosting. So far, this has worked and my media has played without issues.
However, do you think adding something like an Nvidia GPU or driver would solve the issue I’m experiencing?
No. People sometimes try to force fit a GPU into a Synology NAS. It sometimes works, but isn’t supported.
Need to check a couple of things. Will update later today.
The CUDA log entries are normal. I’d not noticed them before on my Synology (DS918+), so wanted to find out more info about it.
Plex is transcoding all the videos to 60 Mbps. That does not make sense and I cannot tell exactly why it is happening. Based on the XML info you attached, the files should direct play. And even if a transcode was needed, transcoding a 2 Mbps video to 60 Mbps makes no sense.
The NAS is running PMS 1.41.5, which is over a year old. You could try updating to the current public version, as there have been many changes over the last year.
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Using Synology Package Center, uninstall Plex Media Server. When presented with the option, choose “Uninstall Only.” This will remove the Plex application. It will not remove the Plex Data Folder (database, etc.) or your media.
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Reboot the NAS.
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Download PMS 1.43.0.10492 from plex.tv. Direct Link: https://downloads.plex.tv/plex-media-server-new/1.43.0.10492-121068a07/synology-dsm72/PlexMediaServer-1.43.0.10492-121068a07-x86_64_DSM72.spk
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Using Synology Package Center, install the Plex Media Server file using the “Manual Install” button.
Plex Media Server will take a bit longer to fully start, as it has to adjust the database to the new version. You may need to give it 2 - 3 minutes longer to fully start before trying to access the server.
Once Plex is fully started, try and play the same video. Play it with both Plex Web and with the Samsung TV (it should direct play for both). If still having problems, pull & post a new set of log files.
Thank you very much for those instructions. I’ll follow the steps tomorrow and let you know how it goes.
I’ve followed your instructions, and I think it’s worked. Instead of 62 Mbps, the video is playing at 9 Mbps, which seems more like it should be?
If you think that’s sorted the issue, then let me express my thanks for how incredibly clear and helpful you’ve been. I really appreciate it.
That looks much better.
However, it still is not clear why the video is transcoding instead of direct playing.
If you would like to keep investigating…
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In the Samsung Plex app, configured it to log to the server at debug level.
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Stop Plex Media Server, wait one minute
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Start Plex Media Server, wait 3 minutes for it to fully log the startup sequence.
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Play the video for 20 - 30 seconds.
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Pull & post the server log files.
Very happy to keep investigating, thank you!
I’ve followed your instructions – here are the log files:
Plex Media Server Logs_2026-04-02_20-47-55.zip (3.7 MB)
Hi there – thanks again for all your help a month ago. My videos are still transcoding, so I’d be very grateful to take you up on your offer to keep investigating! If you need me to share any new log files, let me know. Thank you.
