I recently spent an hour (or three) troubleshooting hardware transcoding on my media server. At some point, an update to the NVIDIA Container Toolkit resulted in CUDA libraries not getting passed through correctly to my containerized Plex installation.

This error appeared in the Plex Media Server.log file every time I attempted to play a file that needed transcoding:

Dec 15, 2024 03:45:14.374 [140307690093368] ERROR - [Req#105/Transcode] [FFMPEG] - Cannot load libcuda.so.1
Dec 15, 2024 03:45:14.374 [140307690093368] ERROR - [Req#105/Transcode] [FFMPEG] - Could not dynamically load CUDA

Running nvidia-smi inside the container also presented the following error: