If anyone knows what's up with this, I'd be forever in your debt; I'm just plain baffled.

A cartoon that I'm working on starts out with a short bit of music and continues with animation that does not have sound, which is then followed by a character speaking. When I drew the character's mouth to sync it to the audio (I'm doing this frame-by-frame), it matches perfectly when I observe the sound wave on the timeline as well as when I play the movie within the Flash interface. When I export or preview the movie, however, my character's voice plays instantly after the music is finished, ignoring the silence I placed in between the two sound files and causing my character's mouth to move several seconds after the sound of his voice has played.

I'm using Flash Pro 8, the sound file is an .mp3, I've tried setting it to "Start," "Stream," and "Event," it's in its own layer, and it's preceded by blank keyframes. Does anyone know what the problem could be?