         playAudioWithRate(2)
     }
     
-    func playAudioWithRate(rate: Float){
-        stopAudioPlaying()
-        audioPlayer.rate = rate
-        audioPlayer.play()
-    }
     
     @IBAction func playChipmunkAudio(sender: UIButton) {
         playAudioWithVariablePitch(1000)


    }
    
    
    @IBAction func stopPlayAudio(sender: UIButton) {
        // MARK: stop play audio
        stopAudioPlaying()
    }
    

}


        stopAudioPlaying()
    }
    
   
    
    @IBAction func playSlowAudio(sender: UIButton) {
        // MARK: play audio slow
