videos won't show after FireFox update.

Hi I'm on windows XP and using FireFox 3.6. I recently had an automatic update to my Firefox , 3.6.21 now. I don't know if was the exact same time but now embeded videos and youtube vids won't play or show.

On older versions of Chrome and IE on my PC, the videos still work so I should be able to keep my current Flash. My Shockwave flash is 10.1.82.76, but I have had problems with my connection performance after updating my flash recently and had to downgrade.

I love the 3.6 Firefox and would prefer not to update to Firefox 6 if I can avoid it. I'm on XP and don't have a dedicated video card so I don't think I need new features for use with newer PC's and OS, and am worried an update will just bring more headaches.
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Is there anything I can check or fix besides updating Flash or Firefox to fix this or is that the only option?

thanks for your help

 

Can you see the Flash animation (rotating red 'f') at http://www.adobe.com/software/flash/about/ ?

What do you see on Youtube instead of the videos?

 

In both cases it's just blank white space.