That complicates things. I would check whether subtitles are enabled (burn-in is notoriously slow) and then try manually adding your server via the app (to rule out wan/relay). Could also recreate the issue and check the server logs - timestamps should tell you what actions were taken when.
Difficult to say without more detail but it’s likely transcoding. You can view how much is cached via tautulli if that’s something you have set up.
Just for lemmy:
Most people on here care more about being right than affecting any sort of progress.
What is the velocity of an unladen swallow?
Just finished Tokyo Vice and didn’t once skip the intro