I’ve recently upgraded my Plex instance to separate out the storage side and the compute side. In general, I couldn’t be happier - the compute side is a little HP prodesk with a quicksync-capable CPU, and the results have been phenomenal.
I have one user who has been complaining about stuttering playback when doing Direct Play on a Roku 3 (2015). When they switch to transcoding, it works perfectly. The only time I’ve seen it, it has been doing a direct stream of MKV -> MPEGTS for the video container with a transcode of DCA 7.1 -> Stereo audio.
Bandwidth is not the issue and they were the only ones streaming at the time.
Do you think the Roku choking on it somehow? My 2017 Shield TV can fully direct play it without issue.
Do you have a similar file to compare it to? Because the only thing I could think of is network bottleneck