Movieclip moves on window minimize

Hello, I have created a button with this function to minimize my application window, in AS3:

function mbtn(e:MouseEvent):void

{

stage.nativeWindow.minimize();

}

On the stage, I have an empty movieclip which loads an AS class file. It works fine and shows up where I have put the empty movieclip which acts as a holder.

But, if I hit the button that minimizes the window, and then open my application again the content of my AS class move some pixels below and go off stage.

How do I fix that?