Anyone got any idea why the following code works perfectly apart from when password number 1 is requested?

stop();

// master array - 2 dimentional
var passwordArray:Array = new Array(new Array("1", "2","3","4","5","6","7","8","9","10"),
new Array("Dave","Mike","Kol","Steve","Pete","Rick","M iles","Ian","Simon","Mark"));

// creates a clone of passwordArray[0]
if (!passwordPool){
var passwordPool:Array = passwordArray[0].slice();
trace("new passwordPool = " + passwordPool)} //refills array if all passwords used.
else if (passwordPool.length == 0){
passwordPool = passwordArray[0].slice();
trace("refilled passwordPool = " + passwordPool);
}

trace("passwordPool = " + passwordPool);
trace("passwordPool.length = " + passwordPool.length);
randomNo = Math.round(Math.random()*passwordPool.length-1); // # between 0-9 - depends whats left in passwordPool
myVar = passwordPool[randomNo-1];
passwordPool.splice(randomNo,1); // removes the element so it cannot be chosen again

trace("randomNo = " + randomNo);
trace("Element removed from passwordPool = " + passwordPool);
trace("Current Password = " + passwordArray[1][myVar]);

nameTxt.text = int(myVar)+1;
pwdTxt.text=""; //clears the input box




checkButton.onRelease = function(){
if (pwdTxt.text == passwordArray[1][myVar]){
trace("Password Matched ");

if (!passwordPool){
var passwordPool:Array = passwordArray[0].slice();
trace("new passwordPool = " + passwordPool)} //refills array if all passwords used.
else if (passwordPool.length == 0){
passwordPool = passwordArray[0].slice();
trace("refilled passwordPool = " + passwordPool)}

trace("passwordPool = " + passwordPool);
trace("passwordPool.length = " + passwordPool.length);
randomNo = Math.round(Math.random()*passwordPool.length-1); // # between 0-9 - depends whats left in passwordPool
myVar = passwordPool[randomNo-1];
passwordPool.splice(randomNo,1); // removes the element so it cannot be chosen again

trace("randomNo = " + randomNo);
trace("Element removed from passwordPool = " + passwordPool);
trace("Current Password = " + passwordArray[1][myVar]);

nameTxt.text = int(myVar)+1;
pwdTxt.text = "";
_parent.password_mov._visible = false;

}
else{
pwdTxt.text = "";
trace("Password Didn't Match ");
gotoAndStop(2);
}

}