Jerky MJPEG playback in 6.1
 

Since I upgraded to 6.1 I have got a more jerky video playback
I have to set video playback to highest mode to get is as smooth as I had in 5.5.3 with medium setting.
Actually..the video playback in 6.1 is so jerky with medium setting that it is impossible to work with.

Why is this ?

I am using a low cpu demanding MJEG compression from Quicktime and my computer is very fast.
It shouldn´t make any difference.

Christian