      */
     public function get isLoading():Boolean
     {   
+        if (!sound)
+            return false;
+        
         return source is Class ||
                sound.bytesTotal > 0;
     }

        
        resumedPosition += pausedPosition;
        
        _soundChannel = sound.play(resumedPosition, loops, pausedTransform);    
        _soundChannel.addEventListener(Event.SOUND_COMPLETE, soundCompleteHandler);
    }
    
    /**

        {
            return duration;
        }
        else if (sound == null)
        {
            return 0;
        }
        else
        {
            // Include the number of loops .
