Can I create a movie file including synchronized sound?

[fs (Frank Scherbaum)]

I am using Mathematica to generate a movie which shows a cursor moving across a spectrogram. I want to combine this with the sound trace from which the spectrogram was calculated such that the cursor is always at the position of the playhead of the sound (see also my question: Can I display the position of what I hear using EmitSound[] ? ). Therefore the non-synchronisity of EmitSound[] and Animate[] is a problem. Using an external program (e.g. quicktime pro) works but requires lots of interaction which becomes problematic for the number of movies I want to generate. I had hoped that some (even undocumented) feature in exporting a video would allow to combine a video track with a audio track.