DS418Play - trouble playing 4k video - constant buffering

ZenMonkey · April 20, 2018

I bought a Synology DS418Play and installed Plex on it by downloading the app from the Plex website and manually installing it, which I read was the suggested method. Then I hooked it up to my network via both network ports, and uploaded a 4k video to test, which the description says it can handle: it actually says it can handle two at the same time. Then I went to my 4k TV, which is hooked up to my XBox One S as a media server. I launched the Plex app on my XBox and played the video. It played for about 30 seconds, then buffered for 3-5 seconds, then played for about 30 more seconds, and repeated. I watched about 10 minutes of the video to see if it would get better, but it didn't. I then tried my phone, which is only 1080p so the video was downsized, and the same thing happened, so I thought maybe it was the wifi and plugged my XBox into my router physically, but the same thing happened.

Are there some settings I can tweak to make this work, or should I just return the thing for false advertisement?

tHe Admirer · April 20, 2018

Was the file, you tested with, an 8bit or 10bit file?

On a side note, I used my i7 770k pc as plex server. I was unable to stream 4K content to my TV. Also buffering the whole time. So, did some research and ended up getting a HTPC with a GT 1030 in, because I needed 4K HVEC 10bit decoding. My setup is now perfect, using a Dell 3040 with I3 6100, 8GB ram and a GT 1030. I have tested numorous media players and they all failed at 4K.

So, first of all, I would say the issue is with your TV and Xbox, but IIRC the Xbox should be able to do HVEC decoding.

tikker · April 20, 2018

Is you network capable of handling 4k streams? Also, probably more important, check in the Plex server activity whether it is Direct Play-ing the file or transcoding. If the latter, than it's no surprise that it's buffering.

It also depends on the type of file you are trying to play, e.g. H264 vs HEVC, 8-bit vs 10-bit, Mbps (https://forums.plex.tv/discussion/296528/ds418play-hardware-transcoding )

ZenMonkey · April 20, 2018

Someone on Reddit suggested I activate hardware transcoding in the Plex server settings. That seems to have resolved the issue. At the very least, I was able to watch one 4k video over WiFi without any buffering except when I skipped around. This was an H264 mkv file. I have an H264 mp4 file and an HVEC 10-bit mkv file tht I want to test next.

There seemed to be a little pixelation during high action scenes, so I'll test a couple more movies and decide whether to hardwire the XBox to my router.