Sound on my video does not activate

hello all…i have a weird one here:

i have a video component that loads an flv into it…when i publish this file, and view it stand alone, it plays the audio track fine…however, once i place it into my site structure the audio gets finicky

basically, at the front end of the site, there is a long flash animation intro…once that finishes, it then loads the swf that has the video component in it…if you let the intro play out to its end, when it loads the swf with the video, the audio does not play…you have to actually click the global audio on/off button (off then on again) to hear the audio

here’s the other weird part, if you skip the intro, the audio plays fine??

STRUCTURE
–it is all published in flash 7
–the flv is loaded into a MediaDisplay component (i tried embedding it and it made no difference)
–the audio on/off is used with the following code:

on the root shell file of site’s timeline:

var global:Sound = new Sound(this);

on the on/off button on same shell file:

//off
_root.global.setVolume(0);
//on
_root.global.setVolume(100);

i am totally stumped on this one folks and would LOVE any help/suggestions

thanks for your time!