Change Pitch Rate of Sound in Swift - XCode 6.4

PlaySoundsViewController.swift

var engine: AVAudioEngine!
var file: AVAudioFile!

override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    
        engine = AVAudioEngine()
        audioFile = AVAudioFile(forReading: filePathUrl, error: nil)
}

func playSound(value: Float, rateOrPitch: String){
        var audioPlayerNode = AVAudioPlayerNode()
        
        audioPlayerNode.stop()
        engine.stop()
        engine.reset()
        
        engine.attachNode(audioPlayerNode)
        
        var changeAudioUnitTime = AVAudioUnitTimePitch()
        
        if (rateOrPitch == "rate") {
            changeAudioUnitTime.rate = value
        } else {
            changeAudioUnitTime.pitch = value
        }
        
        engine.attachNode(changeAudioUnitTime)
        engine.connect(audioPlayerNode, to: changeAudioUnitTime, format: nil)
        engine.connect(changeAudioUnitTime, to: engine.outputNode, format: nil)
        audioPlayerNode.scheduleFile(audioFile, atTime: nil, completionHandler: nil)
        engine.startAndReturnError(nil)
        
        audioPlayerNode.play()        
}
    
@IBAction func playChipmunkEffect(sender: UIButton) {
        playSound(1000, rateOrPitch: "pitch")
}

@IBAction func playDarthVaderEffect(sender: UIButton) {
        playSound(-1000, rateOrPitch: "pitch")
}

@IBAction func playSoundSlowly(sender: UIButton) {
        playSound(0.5, typeOfChange: "rate")
}

@IBAction func playSoundFast(sender: UIButton) {
        playSound(1.5, typeOfChange: "rate")
}
    

hey brother, I'm using this coding for changing the pitch but now what should i do for saving that pitch changed audio any solution i m new in iOS pease help..

Hi, did you find solution for this problem. Can you share with us