Trying to remove movie clip with removeChild

Hi i am trying to remove this movie clip when i want to play another one, i can navigate to the other movie clips but the sound that is embedded in my .swf files will not turn off off, since i have sound in several .swf files when i play more than 1 .swf movie the sound from the files will overlap each other, i have tried removeChild to no avail, any thoughts would be greatly appreciated

This is the code i am using inside my loader timeline:

var myLoader2:Loader = new Loader();
var url:URLRequest = new URLRequest(“images/longsfinal.swf”);