Problem with YouTube, DailyMotion, MetaCafe, or Flash Video Not Playing or Stops After a Few Seconds in Firefox?
Problem: When viewing Flash video streaming content in Firefox 2 or 3 on video hosting sites, such as YouTube, MetaCafe, DailyMotion, Vimeo, Veoh, Revver, iFilm, GoFish and others, or on web pages that embed Flash code from these video sharing sites, the streaming video is not playing, or stops playing after 1 to 3 seconds.
Solutions: The easiest temporary fix is to clear your cache in Firefox, then restart the browswer. Having too many Firefox windows open can make the problem more likely to recur.
A better fix is to download the latest Flash player from Adobe, currently Flash version 10 Beta.