I run Jellyfin on my home server, and this has been a problem for me as well. Even within my home network I'll have occasional stuttering while watching movies, despite the fact that I'm using a dedicated server with 128gb of RAM and 12 CPUs, with a 10 gigabit network card in a 10 gigabit switch, and I'll still get stuttering.
I've debated moving to Plex but I'm broadly against running proprietary software on a server (for reasons I cannot honestly articulate terribly well).
I've debated moving to Plex but I'm broadly against running proprietary software on a server (for reasons I cannot honestly articulate terribly well).