title: Audio from URL not playing with AVPlayer
body: <p>I want to reproduce an audio file hosted in my server when pressing a button. When I press it nothing happens, this is my code: </p>
  
  <pre><code>@IBAction func Reproducir(sender: AnyObject) {
  
      let urlString = "http://...com/marchas/\(pasarid).mp3"
      let url = NSURL(string: urlString)
  
      let avPlayer = AVPlayer(URL: url!)
  
      avPlayer.play()
  }
  </code></pre>