Strange problem with video embeding

Hi,

When I paste a URL from YouTube into my posts it works sometimes.

http://bakapad.com/?p=211 (like this)

Other times it doesn’t…

http://bakapad.com/?p=194
(you can see the URL in text form near the bottom of the post)

Can you tell me why?
WooThemes said it might be a WordPress problem.

Thanks

Fran