void Start()
    {
        GameObject gameControllerObject = GameObject.FindWithTag("GameController");

        if (gameControllerObject != null)
        {
            gameController = gameControllerObject.GetComponent <GameControllerSingle>();
        }
        if (gameController == null)
        {
            Debug.Log("Cannot find 'GameController' script");
        }
    }
 // Use this for initialization
 void Start()
 {
     gameController       = controller.GetComponent <GameControllerSingle>();
     WarningSpeakerSource = WarningSpeaker.GetComponent <AudioSource>();
 }