It runs fine with
softhddevice -v nvdec
For this, next to the Nvidia display driver, also CUDA (e.g. cuda_12.2.1_535.86.10_linux.run) has to be installed.
Next an ffmpeg (git) configured with "--enable-cuda-nvcc" is needed.
I installed all Nvidia drivers manually to avoid conflicts
I have the idea the picture looks better compared with vdpau