Plex in Docker problems during transcoding

[oRBIT]

Tried installing Plex through Container Manager, works good. Until I try to connect and play videos through my iPhone on cellular network. It starts to transcode (on my DS923+) and it spins for awhile. Plex app on phone (iPhone 16 pro) crashes but transcoding continues on the server. Playing through WIFI is fine though.
Anyone knows what's up with this?

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[Rusty]

923 cpu will not play well when transcoding is in question (no QuickSync support). What’s the CPU % while transcoding?

 

[Birdy]

Plex NAS Compatibility

 

[oRBIT]

I'm pretty sure CPU is not the issue since Plex in the standard DSM app does it just fine (more or less 100% CPU on 1080p but still it playbacks fine on my phone ).

 

[Rusty]

more or less 100% CPU on 1080p

Well that is not normal and it is a thin line between "it works" and "won' play".

The fact is that if you are inside your lan via wifi the transfer could be "direct play" depending on the device. Outside your house if there is no port forwarding, and the CPU has no QS capabilities (as is the case with 923), your playback will be transcoded for sure, and the issues will start to pop out.

Best to check the Plex dashboard while streaming is running (even with issues), and you can check the stats as well as the playback card that will say what is happening with video, audio and subtitles (if in use).

 

[oRBIT]

I perhaps expressed myself badly:

• In the same network (wifi), directplay is working, no transcoding. No CPU usage.
• If I disable 4G/5G on my phone to simulate that I am out of the house, then Plex obviously requires (software) transcoding, then the CPU starts to work. And then the app crashes (using docker-Plex only, DSM-spk Plex works fine)
• When using Plex Web, transcoding works fine aswell.

 

[oRBIT]

Strange, now it works! I am not aware I did anything with the settings... Let's hope it continues to work..