Could be either. We've seen bugs specific to certain models and even entire brands (Sony when playing Dolby Vision). But its hard for the devs to test if they don't own the TV.
Jellyfin 10.10.1 (Docker)
Ubuntu 24.04 LTS
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
3x WD Red Pro 6TB CMR in RAIDZ1 (JF Library)