HELP! Feedback buzz on some portions of video

[MrRoboto]

I apologize in advance for not being very technical, but I am creating a video that runs approximately twenty minutes before a program at my work and having trouble with a feedback buzz coming through in portions of the video.

I am using Windows Movie Maker to create the video and haven't had any problems in importing, editing, adding transitions, etc. The first 15 minutes of the video consists of a still image with the title of the event and a photo of the woman who will be speaking. The still image is just a regular jpeg. For the audio track, I've just got general mood music playing over it that people will listen to as they're filing into the program (these are wma rips from CDs I made using Windows Media Player). At about the 14:30 mark, I put in a dissolve transition that fades the scene to black for about 30 seconds. At this point we'll turn the house lights down without announcement and that'll signal people to take their seats. At the 15 minute mark, the last song (audio track) fades out and a 5 minute video starts. The woman speaking is a dancer and the 5 minute video is a video of her dancing. The video is an avi file. I was able to import all of the files, edit them together on the timeline, add transitions, etc. and record it to DVD. However, when I play it back on our overhead broadcast system from either of our two DVD players, there is a buzzing feedback noise that plays over the still image that runs from 0:00 to 14:30. When it fades to black, the buzzing goes away. When it transitions to the dance video, the buzzing seems to come back whenever there's a prominent flash of light in the video. My guess is that I'm getting audio noise from the video track. Unfortunately, I don't know how to fix the problem. And I can't hear the feedback on my computer when I'm editing and playing it back there. The feedback buzzing is only evident when I play it on a our overhead broadcast system from a standalone DVD player. And I have no way of changing any settings on that broadcast system. My options there are pretty much Play, Stop, FF, Rewind and Eject.

Any ideas or suggestions on how to help in re-recording the video to edit out the feedback? I thought of pulling the Audio Levels setting on Windows Movie Maker down so that I'm only getting audio from Audio/Music, but then when I add the dance video (which has its own music track), I'd probably want it to be the opposite setting. But I'm not sure if that's right or even how to do that.

[lowellriggsiam]

Post a clip with the issue, possibly the point of transition ~1 min so we can better assist you.