2023-09-28, 12:51 PM
This sounds like a client side bug. IMO, your two options are to select a lower bit rate to force transcoding (if you have "Allow encoding in HEVC format" checked, uncheck it) or perhaps give the beta version of the Jellyfin Android TV app a try. You're not the first person with this kind of issue on a Firestick.
https://github.com/jellyfin/jellyfin-androidtv/releases
https://github.com/jellyfin/jellyfin-androidtv/releases