I took a look and they're streaming ok for me. However I noticed that they're loading kinda slowly and glitching slightly.
Usually this means that the server is backing things up or doing maintenance.
I'm not totally sure how long it takes but I know sometimes when I'm going through videos they only partially play and have to catch up before they continue.
It used to happen in the early hours of the morning because it was assumed that was when the least amount of people were using the system.

The only thing I can think is the server might be backing up when it's doing that and you might have to wait, or just download it in it's entirety first.

If you continue having problems though send a note to tech support or call them & they'll figure things out for you.