Bubbles - duplicate problems

[swordfish123]

Hi!

I'm working on a application with some bubbles. Each bubble goes from the bottom to the top. It works just fine with just one bubble, but when I duplicate the bubble it just stops on it's way towards the top. I want to have many of them, with different properties.

Could there be a "level" problem or?

Here's the code:

function createBubble(){
	i++;
	scale = random(120) + 30;
	xMove = random(10)+1;
	yMove = random(30)+1;
	bubble = bubble_mc.duplicateMovieClip("bub" + i, i);
	bubble._xscale = scale;
	bubble._yscale = scale;
}

my_btn.onPress = function(){
     //myBubble = setInterval(createBubble, random(3000) + 100);
    createBubble();
}

this.onEnterFrame = function() {
	
		bubble._y -= yMove;		
		bubble._x = Math.sin(a) * xMove + 150;
		a += 0.2;

		
		if(bubble._xscale > 0){
			bubble._xscale -= scaleFactor;
			bubble._yscale -= scaleFactor;
		}
		
		if(bubble._y < 0){
			removeMovieClip(bubble);
			createBubble();
		}

	
}

Thankful for some advice
/S-fish