title: Play sound with a little delay
body: <p>I have a sound in my app that starts automatically when appear the view; but, as the title says, I'd like that this sounds starts with a little delay, about an half second after the view appear. I tried to use PlayAtTime, but or it does not work or I have set somethings wrong...
  This is my code:</p>
  
  <pre><code>var player = AVAudioPlayer?
  override func viewDidLoad()
  {
      super.viewDidLoad()
      playAudioWithDelay()
  }
  
  func playAudioWithDelay()
  {
      let file = NSBundle.mainBundle().URLForResource("PR1", withExtension: "wav")
      player = AVAudioPlayer(contentsOfURL: file, error: nil)
      player!.volume = 0.5
      player!.numberOfLoops = -1
      player!.playAtTime(//I tried with 0.5 but doesn't work)
      player!.prepareToPlay()
      player!.play()
  }
  </code></pre>