[compiz] Compiz slow when playing some videos?

[Bellegarde Cedric]

Currently, compiz really deal well with most videos...

But some videos make compiz slow...
ex:
ftp://ftp.developpez.tv/tv/linux/2007/solutionslinux/Keynote2.ogg

Play it, try to move the window, you will have artefact...
Let the video play, launch firefox/konqueror, move the window, it will not be 
smooth :( With some others videos, no problem.

GeForce 7600 with nvidia drivers
Wobbly activated
detect refresh desactivated (doesn't work here)
sync to vblank enabled

Compiz launched with: /usr/bin/compiz --loose-binding --replace gconf

Cedric