iMovie 10 importing one good and one bad version of each clip

I imported all of my video from iMovie 9 to iMovie 10 and have found that most events have duplicates of each clip with the first one being good, normal quality and the second being really bad quality (highly pixelated video like this: http://d.pr/i/w86E). The sound seems to be fine on both.

Has anybody else run into this problem and is there a way to fix it?

Thanks