[8.04 amd] kaffeine movie jumps when ever window is redrawed (nvidia binary)

[LimCore]

When playing a video in kaffeine, it starts to jump like crazy when ever the playe window is redrawed;

Either:
- resize the window (best with mouse)
- move the window
- move other windows over (partially hiding) the player window

and then the sound plays ok, like 1,2,3,4,5,6,7,8,9,10,11,12.... frames
but the video start to jump strangelly for around 2-4 secounds, the frames are played like:
1, 11, 3, 13, 5, 15 frames sort of (it jumps forward and backwards a bit)

Nvidia (gt8600) binary driver
SMP, amd64
using regular 2d desktop only (kde)
up to date system

no errors in Xsession-errors