How to know if sound is playing?

1

So I have this sound object, and want to stop it.


channel.stop(); //which does nothing at all....

sound.close(); //which throws an error "no soundstream etc etc"

My code


var sound:Sound = new Sound();
var channel:SoundChannel = new SoundChannel();

public function listen_mp3(url){
	stop_all();
	sound.load(new URLRequest(url));
	channel = sound.play();
}

public function stop_all(){
	channel.stop();
	sound.close();
}

Regards