Volume control

I’m trying to create a volume control slider for a media player. I used the tutorial on kirupa but it only plays when you hit play. On my own player, I can get it to where it plays right when the movie starts but you hear no sound unless you click on the dragger (which is set at 100 when the movie starts). How can i get it to not be muted at the start? thanks!

here the tutorial i used: