Why is my editor's XML out of sync?

I sent my XML an editor to work with. For some reason, the audio is out of sync. I can't quite figure out the problem. The time codes for the video and audio are correct, but as the film goes on it gets out of sync. It starts fine. 

I cannot figure out what the problem might be. The sample rate for the audio is right. And when i play it on my computer, everything is playing OK.

Any ideas what might be going wrong?