We've been hearing that some customers are experiencing issues with Video Players not working correctly.  We've tested our service and neither Moonfruit nor the software are causing the problem.

What we are hearing through the grapevine (unconfirmed at present) is that on Saturday afternoon Google released a big update for Flash/HTML5. This appears to have generated a bug which has impacted a large number YouTube videos - producing sound and no pictures.

Update: This has been fixed by Google.