[Invalid] YouTube Video takes 10 seconds to unblock

[linux64user]

When I click on blocked video on Youtube my Firefox seems to hang (tabs cannot be switched) and I have to wait about 10 seconds before playback starts.
This occurs only in Ubuntu, both 32bit and 64 bit, and even with beta native 64-bit libflashplayer.so
Firefox 3.6.10 (really occurs on all 3.5-3.6)

Any help is appreciated
Cheers, Vladimir

[linux32yser]

Can't reproduce in 32bit Lucid.
NS 2.0.3.2
youtube.com not whitelisted
Forbid Adobe Flash checked

Steps taken:
With 5 tabs open
navigated to http://www.youtube.com/watch?v=6lG6LWGiIE4 in a 6th tab
selected placeholder, selected ok
Video began playing immediately and other tabs were all available for use.

Processor: Intel E7400
Memory: heaps of 2GB available.

[linux64user]

Thanks for your reply!
It was caused by Redirect Remover