Audio out of sync when importing video to iMovie

Playing the movie in Quicktime before the import: Perfect

After importing that movie in iMovie: Something happens and the audio is out of sync.

Is there a better method than detaching the audio and constantly moving it around? I'm even having trouble with that solution (and it is very tedious). I'm using iMovie 9.0.4. I know it's a common issue with iMovie, but some of the solutions are kind of outdated or don't apply in the same way.