Well, I recently upgraded to Mac 10.6.3 and got all the new apps with it. Along with it was the new iMovie, so I got to work on a new video of mine. Now, I make an abridged series right? So I take the original video and redub it with my own stuff. So, I get about 4 minutes into it, and it sounds perfectly fine.. so I tried exporting it to see how it ran in Quicktime, and..... well, in about 2 minutes into the file, the audio of some of the clips near the end started playing OVER my own audio, then stopped at about 3 minutes in. I have no idea what's causing this... I have a suspicion though... when I worked on the video, I had to use 2 separate videos, which I imported as two separate events to work on one project, would that have any effect on it? If you would like me to post an example of the video to help determine if you seen something like this before, please say so and I will do it.