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[TheDreadPirate]

Which version of Jellyfin are you running? I'm assuming you are using Docker to run Jellyfin. If you are using the official jellyfin/jellyfin image, version 10.8.13, there was an update to the Intel OpenCL drivers included in that image that depreciated support for Linux kernel 4.4.X. The problem is that a lot of Synology NASes are still running on 4.4.X and Synology has no plans to update DSM with a newer kernel any time soon.