[CS3 AS2.0] Please help with functions

I’m not really a flash programmer and I was hoping someone could help me out. I’m trying to use a floating stage where my menu moves based on the size of the content in the movie clip above it. As of right now its working, but, whenever it moves, it flickers. This is a purely ascetic problem, but is still pretty annoying. anyone know how to fix this?

Here’s a link
http://www.philipscottandrews.com/clarksville/content/

Here’s the actionscript

Stage.scaleMode = “noScale”;

menu.onEnterFrame = function ()
{
var stageXCenter = (Stage.width * .25) - (header._width * .5) + 100;
var stageYCenter = header._height + 20;
var stageYBottom = header._height + player._height + 30;
header._x = stageXCenter;
header._y = 10;
player._x = stageXCenter;
player._y = stageYCenter;
menu._x = stageXCenter;
menu._y = stageYBottom;
}

I’m using Flash CS3 with Actionscript 2.0

Thanks for any Help