Nvjpegdec does not work for USB camera

Hi,
There is a known issue in MJPEG decoding:
Issues with nvjpegdec on live HTTP streams - #3 by DaneLLL

It shall be fixed in next Jetpack 5.1.3. On 5.1.1 or 5.1.2, please use nvv4l2decoder or software JPEG decoder.