Jellyfin can't play videos

Creating a bug report/issue

I have searched the existing open and closed issues

Required Information

  • DietPi version | G_DIETPI_VERSION_CORE=10
    G_DIETPI_VERSION_SUB=2
    G_DIETPI_VERSION_RC=3
    G_GITBRANCH=‘master’
    G_GITOWNER=‘MichaIng’
  • Distro version | bookworm 0
  • Kernel version | Linux DietPi 6.12.75+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.12.75-1+rpt1~bookworm (2026-03-11) aarch64 GNU/Linux
  • Architecture | arm64
  • SBC model | RPi 4 Model B (aarch64)
  • Power supply used | 5V 1A RAVpower
  • SD card used | SanDisk ultra

I have mounted my NAS (Fritzbox NAS) via SMB on my dietpi. I can also find my video folder on my NAS via Jellyfin, which is also installed on my dietpi. But I can’t play any of them:”Playback failed due to a serious player error.”. They are all H.264, so don’t have to activate transcoding right?

thx