Hello Thoralf,
if you're capturing your live video at max resolution, you should try to reduce the resolution ...
I don't know how to reduce the resolution, i could only set the [quality( that means i can change between black/white and color mode and a mode whith very very low resolution. But i've dedected that if i start rendering the first time the performance is bad and the output is somehow zoomed in. If i stop rendering and start it again it's working how it should... Only with a little delay which is acceptable. And the same behaivior is when i playing a film...
lg Christian