         {
             track.removeEventListener(MouseEvent.MOUSE_DOWN, 
                                       track_mouseDownHandler);
+            track.removeEventListener("updateComplete", 
+                                      track_updateCompleteHandler);
         }
     }
 

        {
            track.addEventListener(MouseEvent.MOUSE_DOWN,
                                   track_mouseDownHandler);
        }
        
        enableSkinParts(enabled);

    }

    /**
     *  Adds event handlers to the track and thumb for mouse events.
     */
    override protected function partAdded(partName:String, instance:*):void
