Problem with go to and play

Hi I'm making a simple web with 4 buttons. And i made the respective links, with gotoAndPlay in as3. Everything is working good, but when i click on the last button, the btn 4, and then want to go to the btn 3 it doesn`t work. It only work, when i want to go from button 4 to 2, and 4 to 1. Why is happening this? Here is the code:

stop();
btn1.addEventListener(MouseEvent.CLICK,funcion1);

function funcion1(evt:MouseEvent):void{
    gotoAndPlay(10);
};

btn2.addEventListener(MouseEvent.CLICK,funcion2);

function funcion2(evt:MouseEvent):void{
    gotoAndPlay(20);
};

btn3.addEventListener(MouseEvent.CLICK,funcion3);

function funcion3(evt:MouseEvent):void{
    gotoAndPlay(30);
};

btn4.addEventListener(MouseEvent.CLICK,funcion4);

function funcion4(evt:MouseEvent):void{
    gotoAndPlay(40);
};

PD: I'm sure all the buttons have the instance name in all frames (10;20;30;40)