Server Version#: 1.24.5.5173
Player Version#: Apple TV, Xbox, iOS (iphone)
First, let me get out of the way that I know I can create a second rip of the movie for transcoding to remote users, but that is not the issue at hand here.
I have been running into this issue for a while now where UHD rips will buffer during playback where blu-ray rips will play just fine. I had thought it was a resource issue on my server so I picked up a GTX 1650 and have now enabled hardware transcoding. I am still experiencing the same issue even though nothing in my hardware is being taxed. The encoders on my card are ar 20% and my CPU is at 20% as well when a remote user is streaming UHD. I started thinking it was a bandwidth issue so we experimented with lowering the quality of the remote playback. Lowering the quality setting did seem to decrease the frequency of the buffering but it was still there at 720p 4Mbps. 1080p works fine for my blu-ray rips. I have also tried the following:
- Lowering the playback quality on the remote player
- Changing my upload speed setting in the server
- Setting the remote stream bitrate at the server
- Adjusting the transcoder quality setting
- Increasing the transcoder default throttle buffer
Th reason that I think this is a bug with the transcoder being employed in plex, is the bandwith behavior difference between the transcoder being used for bluray…
…and that being used for UHD…
The UHD transcoder does not keep a sustained data flow to the client like the HD encoder does. Because of this, I think it gets behind, causing the client playback to buffer. Again, my CPU, memory and GPU are not being taxed. When I lowered the max upload bandwidth of my server, the peaks did seem to become lower and more frequent.
Interestingly, I don’t have the issue when connected to my guest wireless network. In this instance, the Plex app on iOS thinks it is remote, but the bandwidth on the server shows as being local. There are no issues whatsoever streaming on the same network, but I have not yet tried decreasing the quality settings to force it to transcode.
