For some reason video thumbnails are not showing up from certain sites that are included in the video plugin. 

Xhamster and pornhub both do not work but the youtube one does.

You can see here at http://www.adultxxxchats.com what I am talking about.

I am not that familiar with php at all so I can only look at the video_providers.php and see that they are there but no clue why they wouldn't be working.

Any help would be greatly appreciated.