mjpeg decoding problem

[ares81]

I tried to watch a mjpeg stream with VLC but I cannot. I use the latest version of VLC. The stream comes via UDP and I am pretty sure the stream is right.
If I look into the statistics, I can see that VLC gets an input bitrate around 500 Kbit/s, but no audio or video is detected. The demultiplexed info is as well zero.

Any ideas? Does VLC support MJPEG? As far as I know it does, but is there any consideration (version, ...) I have to take in account? Do you know any tool to look into the detail the mjpeg packets?

Thank you for your help in advance!