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I arrived in San Francisco to attend Macworld Expo only to be confronted with my first troubleshooting question. A colleague, who shall remain nameless, asked:
I've been asked to record narration over my Keynote presentation. I tried it at home and found that while, within Keynote, I can play back my presentation, complete with the recording of my narration, when I export the results as a QuickTime movie, I wind up with a movie with no sound. Is there a workaround for this?
Regrettably, if you're running the latest version of the Mac OS and Keynote '08, this is not an uncommon problem-Apple's discussion forums are littered with messages like this. The best solution would be for Apple to fix it, but in the meantime there's this option.
After recording your narration, move to the Finder, Control-click on your presentation file, and choose Show Package Contents. In the resulting window, locate the narrationTrack0.m4a file. This is your narration track. Make a copy and move it to the Desktop.
Open both the narration and video files in QuickTime Player Pro. Select the audio track, select everything in it, and copy. Now select the video track and choose Edit -> Add to Movie. The audio track will be added to the video track.
With luck, the two will be in sync. If not, you might wish, instead, to import the video track into GarageBand and then place the audio track in a separate track and move it around so the two are in sync.
Read article at Macworld.com