Transition stutter in Power Director

Hi, I shot an 1hr+ HD video with Nikon Coolpix P7700. It uses Quicktime format. Loaded the files into Power Director and simply cut out unwanted stuff. No other editing. When playing the rendered MPEG file, I get this hesitation after each cut – the last frame of each clip kind of freezes before going on to the next one. What could be the reason?

Thanks!