YouTube Videos - showing as a white box (stream) or not streaming if video image shows

Hi! I've just setup EasySocial and imported everything from JomSocial.

However, I'm having a problem with the imported YouTube videos....

The videos either show as a white box (on the stream) or as an image (in a group video) which, if you click on, do not show the video.

I've attached images of those situations with URLs below in the "Hidden from Public" area.

What should I do?

Thanks. -- Rik