AS3 movieclip problem - mouse speed

Hi, I wonder if anyone can shed some light on this and maybe provide a solution:

I have a movieclip button with a rollover function that goes to the next frame which holds two buttons that can be clicked. It all works almost perfect except that when I test or publish the movie, if I roll over the movie clip really fast with the mouse the functions dont work. It is like I’m moving too fast for flash to trigger the code.

Inside my movieclip I have an invisible border around it, that has a Rollout code that is supposed to return the clip to frame 1 and i think this is the issue because when the mouse moves too fast this action does not trigger.

this is the code i have for the invisible button:

TDinvisible_btn.addEventListener(MouseEvent.ROLL_OUT, f3_RollOutHandler);

function f3_RollOutHandler(event:MouseEvent):void

{
gotoAndStop(1);

}

is anyone able to elaborate on why this is happening and also provide an alternative piece of code that will work regardless of how fast the user moves the mouse?