Using Flashvars to load external mp3 files

Question

I am trying to find a very good step by step tutorial on using "Flashvars" to load external mp3 files, I have been searching on google and the many I have found fall short in some way or another. From what I have been able to gather, I have tried using the code in red (commented out), which works, and modify it to use "Flashvars". The code that works, the mp3 file is hard coded, but my goal is to use "Flashvars" which I am attempting to do in the code following the code in red. I am also including the html code. Any help will be greatly appreciated.
Thanks,
David
var soundReq:URLRequest = new URLRequest("mardi_gras2.mp3");
var sound:Sound = new Sound();
sound.load(soundReq);
sound.addEventListener(Event.COMPLETE, onComplete);
function onComplete(event:Event):void
    sound.play();
var soundReq:URLRequest = new URLRequest(root.loaderInfo.parameters.audio);
var sound:Sound = new Sound();
sound.load(soundReq);
sound.addEventListener(Event.COMPLETE, onComplete);
function onComplete(event:Event):void
    sound.play();
HTML CODE
<object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=9,0,0,0" width="550" height="400" id="mySoundvars" align="middle">
    <param name="allowScriptAccess" value="sameDomain" />
    <param name="allowFullScreen" value="false" />
    <param name="movie" value="mySoundvars.swf" />
   <param name="FlashVars" value="audio=mardi_gras2.mp3" />
    <param name="quality" value="high" /><param name="bgcolor" value="#ffffff" />    <embed src="mySoundvars.swf" quality="high" bgcolor="#ffffff" width="550" height="400" name="mySoundvars" align="middle" allowScriptAccess="sameDomain" allowFullScreen="false" type="application/x-shockwave-flash" pluginspage="http://www.adobe.com/go/getflashplayer" FlashVars="audio=mardi_gras2.mp3" />

Answer 1

Ok waterlovinguy,
I went back to my original code, and I got things to work... I think my whole issue was with the HTML CODE. So I decided to use the "SWFObject generator". I had never used it before, frankly I had never heard of it until I started my searches on "Flashvars".
Thank you very much for all your assistance, PEACE,
David
Final Codes below
var my_var:String = new String();
my_var = root.loaderInfo.parameters.myflashvar;
myText.text = my_var;
var soundReq:URLRequest = new URLRequest(root.loaderInfo.parameters.audio);
var sound:Sound = new Sound();
var soundControl:SoundChannel = new SoundChannel;
sound.load(soundReq);
play_btn.addEventListener(MouseEvent.CLICK, playSound);
stop_btn.addEventListener(MouseEvent.CLICK, stopSound);
function playSound(event:MouseEvent):void
    SoundMixer.stopAll();
    soundControl = sound.play();
function stopSound(event:MouseEvent):void
    soundControl.stop();
HTML Code
                <!>>
                <!<![endif]>
                    http://www.adobe.com/go/getflashplayer
                    </a>
                <!>>
                </object>
                <!<![endif]>
            </object