We've recently setup jomsocial, and been trying to get the video part up.
so far, we've not been succesfully in uploading mp4 format -- it pops up saying mp4 not supported. But I remember reading through the documentation/or i think i saw a video tutorial -- shown they can upload mp4.

if upload .flv file, then it's ok. but then no video thumbnail shown. :(

pls assist.

Hi, Sher Khan.

I uploaded mp4 file without any issues or notices: prntscr.com/3yku08
I uploaded file that is attached to this post.

I don't see flv video that you tried to upload...there is only YT video in All Videos and my test in Pending Videos.

As I can see files are not converted: prntscr.com/3ykuq2

So make sure that FFMPEG is installed on your server.
Check path to it if it's correct.
Ask your hosting provider for assistance and ask what version of FFMPEG is installed (if any).