What's the best way to attach a large sound file?

I want to attach a sound file and have several cuepoints that will cause certain movies to play as the sound file plays.

I’ve looked into this and think I’m right in saying that you can’t have an external sound file, like you can have an external Flash video file?
Is this true?

What would be the best way to attach my large sound file?

One way which I thought I could do what I need: create a Flash video file, don’t show the video file and just play it… and then use Flash video’s cuepoints.
Is this a good way to do what I want?

Any help would be appreciated.