Help! I am running out of time!

I have this background music that plays and i am loading that using the

myMusic = new Sound();
myMusic.start(0, 1000);

option, and i start the music, now once the user clicks a buttons saying presentation, he goes into the section where the MPG movie starts

tellTarget ("/myMpgmovie") {

and i reduce the volume of the background music, like a fade effect every five frames using the s.setVolume(90)…till i use s.stop(),

then what happens is my MPG movie clips volume also cuts off, now how can i avoid that from happening, please help pls, i’ve been spending few days trying to figure it out using all other methods, still, i’ve not come out with better solution.

Thanks in advance