mp3 playback stop echoing, as3

Hitting play more than once, causes an echo and I can't stop my mp3 player. What's the best practice for mp3 playback?

            var mySound:Sound = new Sound();
    playButton.addEventListener (MouseEvent.CLICK, myPlayButtonHandler);
            var myChannel:SoundChannel = new SoundChannel();

            function myPlayButtonHa开发者_高级运维ndler (e:MouseEvent):void {
                    myChannel = mySound.play();
                            }
    stopButton.addEventListener(MouseEvent.CLICK, onClickStop);
            function onClickStop(e:MouseEvent):void{
                            myChannel.stop();
                            }

Here are two buttons to control volume globally. Let me know if this doesn't work.

var mySound:Sound = new Sound();
playButton.addEventListener (MouseEvent.CLICK, myPlayButtonHandler);
var myChannel:SoundChannel = new SoundChannel();
        function myPlayButtonHandler (e:MouseEvent):void {

            myChannel = mySound.play();
            }
stopButton.addEventListener(MouseEvent.CLICK, onClickStop);
        function onClickStop(e:MouseEvent):void{
            myChannel.stop();
            }

/*-----------------------------------------------------------------*/
//global sound buttons, add instance of 'killswitch' and 'onswitch' to stage
killswitch.addEventListener(MouseEvent.CLICK, clipKillSwitch); 
        function clipKillSwitch(e:MouseEvent):void{ 
var transform1:SoundTransform=new SoundTransform();
transform1.volume=0;
flash.media.SoundMixer.soundTransform=transform1;
            }       
onswitch.addEventListener(MouseEvent.CLICK, clipOnSwitch); 
        function clipOnSwitch(e:MouseEvent):void{ 
var transform1_:SoundTransform=new SoundTransform();        
transform1_.volume=1;
flash.media.SoundMixer.soundTransform=transform1_;      
            }

I would do several things.

1. Once play is hit, record that state in a var. Then if they hit play again, don't do anything if you are already in the 'play' state.

Another option: 2. Change the playbutton to a pause button. Then perform the stop action if the button is hit, instead. If they then hit pause, then switch the button back to play.