Why is my frame-rate lagging?

I'm using Flash MX 2004 at the moment, and I've made an animation that is 
synced to music, but when I 'test movie' or 'publish', the frame-rate slows 
down and the music becomes un-synced. How do I fix this?

I wish I knew the answer, but I do know a way to solve it (sort of). In your 
publish settings, under the HTML tab, change the Window Mode to Opaque 
Windowless or Transparent Windowless. You can choose either one. Then 
re-publish/test.

 I don't know why this fixes it, but it does. The only downside to this, is 
that you can kiss your mac users goodbye. This causes your swf to lag even 
worse on a mac.

 Hopefully this help, but hopefully someone can provide a better answer.

 GAMBRKER

That's not making any difference.

I don't think the version will matter.  My only other suggestion is that you 
are overloading your computer's processor with too much stuff on the stage, or 
tweening too many things at one time, or tweening something very large.