How to resume background audio in Swift 2 / AVPlayer?

Finally got it!

Solution: added the mixable option by changing the setCategory line to be:

AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback,
                                            withOptions: .mixWithOthers )

I wrote a code like this and successfully resumed the audio from the phone call ended. I was build on Xcode 6.4 and ran the app on my iPhone 4S.

var player: AVQueuePlayer! = nil

override func viewDidLoad()
{
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

override func viewDidAppear(animated: Bool)
{
    super.viewDidAppear(true)

    var song = AVPlayerItem(URL: NSBundle.mainBundle().URLForResource("AlmostAYearAgo", withExtension: "mp3")!)
    player = AVQueuePlayer(items: [song])

    let theSession = AVAudioSession.sharedInstance()

    NSNotificationCenter.defaultCenter().addObserver(self, selector: "playInterrupt:", name: AVAudioSessionInterruptionNotification, object: theSession)

    player.play()
}

override func didReceiveMemoryWarning()
{
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func playInterrupt(notification: NSNotification)
{
    if notification.name == AVAudioSessionInterruptionNotification && notification.userInfo != nil
    {
        var info = notification.userInfo!
        var intValue: UInt = 0

        (info[AVAudioSessionInterruptionTypeKey] as! NSValue).getValue(&intValue)

        if let type = AVAudioSessionInterruptionType(rawValue: intValue)
        {
            switch type
            {
            case .Began:
                print("aaaaarrrrgggg you stole me")
                player.pause()
            case .Ended:
                let timer = NSTimer.scheduledTimerWithTimeInterval(3, target: self, selector: "resumeNow:", userInfo: nil, repeats: false)
            }
        }
    }
}

func resumeNow(timer : NSTimer)
{
    player.play()
    print("attempted restart")
}