[PD] Gem - pix_invert - only bottom 1/3 of image gets processed!

[robcanning]

Hello,

while i am at it - bombarding the list with my problems - here is 
another one!  sorry:-)

in XP with the latest stable PD and Gem if i use:
pix_video_ds > pix_invert > pix_texture2 > square 4
for example, only the bottom third of the my webcam  feed gets 
processed by pix_invert in the gem window.
I don't have this problem in OSX with the same patch (but using 
pix_video instead of pix_video_ds)
Anybody got and ideas why this is happening?

Thanks,
Rob