Welcome the Technical Support section. Help us in assisting you by providing us with a concise and descriptive elaboration of your issues. Be specific and if possible, provide us with a step-by-step instruction in replicating your problem.
I use the latest Jomsocial (4.4.3) with Joomla 3.7.5 and the video upload does not create the stream activity.
The video is converted and posted on My Videos correctly by cron, but no activity is created.
Is this a bug on this version?
I've tested on 2 different sites with the same results.