When I make a movie the animation is shaky/shivering.

What I do:
I set the speed of the movie to 30 fps.
I draw a filled circle and add a keyframe.
I add a second keyframe and move the circle to the right.
I have tried different settings for the number of tweens between the keyframes. High, low, it does not matter.

When I play the animation it is like the tweens catched a cold. The general movement is smooth. The object itself is shivering/ghosting allong the way. Don't know what to call it.

The response time of the monitor is 2ms. That should be fast enough to prevent some kind of tearing.

Is there something I am missing?

Thanks.