I have iMovie '09 version 8.0.6. Just finished a project, that I've done a few times before. It's a montage of friends singing, with one song over all of the clips. I detach and delete the audio from every clip, and just use one song from my iTunes. Easy enough. However, when I export via Quicktime, and I keep hearing background noise on certain clips in the Quicktime movie, but not in iMovie. I went back and deleted the audio from every single clip, several times, but the background noise keeps coming in over the song I've chosen from my iTunes. I've tried to fix it, 6 different ways and nothing is working.

Please help!