Menu button flickering

I made a menu bar with 6 items. The first 5 work just fine, but the last one is giving me trouble.

When a button is clicked the user is forwarded to a different webpage, but the 6th button doesn't do anything. I have a mouse "over" animation on all the buttons and it seems that when I mouse over the last button the animation is just flickering. But when I move the mouse over the text it works like it is supposed to, i've tried changing hte hit box but it doesn't seem to do anything.

Also when the button is clicked it just continously flickers.This is the code for the menu:

stop();
homebtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_1);
eventbtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_2);
csbtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_3);
mediabtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_4);
contactbtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_5);
sponsorbtn.addEventListener(MouseEvent.CLICK, fl_ClickToGoToWebPage_6);
function fl_ClickToGoToWebPage_1(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest("index.html"), "_self");
}
function fl_ClickToGoToWebPage_2(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest("../../events/"), "_self");
}
function fl_ClickToGoToWebPage_3(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest(../../cs/"), "_self");
}
function fl_ClickToGoToWebPage_4(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest("../../media/"), "_self");
}
function fl_ClickToGoToWebPage_5(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest("../../contact/"), "_self");
}
function fl_ClickToGoToWebPage_6(event:MouseEvent):void
{
  
          navigateToURL(new URLRequest("../../sponsors/"), "_self");
}

Thank you! I'm not sure how to post the .swf or .fla but I can email it if needed.