VideoPad v7.01
If I take a clip (.mp4, 1280x720, 240fps), set the speed to 30% and export (.mp4, 1280x720, Variable Frame Rate (Max 48fps)), then the result is fine, i.e. as you would expected.
If I apply the video effect "Auto Levels" and do everything else exactly as above, then the result is choppy. It looks rather like a video with 10 fps or less.
The same happens with the video effect "Temperature" and probably some other effects.
Any ideas how this can be resolved?