Loading Screen Music Volume

So i want to turn down the volume of the music on my loading screen. does anyone know how to fix this :S ?

<object style="height: 1; width: 1"><param name="movie" value="http://www.youtube.com/v/Yw4rMtzqR38?version=3&autoplay=1&loop=1">
<param name="allowFullScreen" value="true">
<param name="allowScriptAccess" value="always">
<embed src="http://www.youtube.com/v/Yw4rMtzqR38?version=3&autoplay=1&loop=1" type="application/x-shockwave-flash" allowfullscreen="true" allowScriptAccess="always" width="1" height="1">

Thats what i use to play my music atm

if you are using a sound file, lower the sound volume using amplify or something, but if its a video or website, it’s pretty much like that i think.