Question When Viewing .swf's Online

Hello there,

Is there any reason why my Flash movie is moving slow? I have 4 very simple shape tweens in the first 35 seconds of my movie, along with a preloader, and some test content. I know where some of the end content should be, because I have an .mp3 which is playing along with the animation. Everything sync’s well from where I want it to when viewing on my computer, but after uploading it doesn’t sync anything like it should, and in fact looks like its running at a slower FPS (I have mine set at 30).

What would cause such a slowdown when I know the way I have this built is the same on other sites I can see right now, and they look fine?