         _avTransportEventObserver = newRenderer?.avTransportService()?.addEventObserver(NSOperationQueue.currentQueue(), callBackBlock: { (event: UPnPEvent) -> Void in
             if let avTransportEvent = event as? AVTransport1Event {
                 println("\(event.service?.className) Event: \(avTransportEvent.instanceState)")
-                if let transportState = avTransportEvent.instanceState["TransportState"] as? String {
+                if let transportState = (avTransportEvent.instanceState["TransportState"] as? String)?.lowercaseString {
                     println("transport state: \(transportState)")
-                    if transportState.lowercaseString.rangeOfString("playing") != nil {
+                    if transportState.rangeOfString("playing") != nil {
                         self._playerState = .Playing
                     }
-                    else if transportState.lowercaseString.rangeOfString("paused") != nil {
+                    else if transportState.rangeOfString("paused") != nil {
                         self._playerState = .Paused
                     }
-                    else if transportState.lowercaseString.rangeOfString("stopped") != nil {
+                    else if transportState.rangeOfString("stopped") != nil {
                         self._playerState = .Stopped
                     }
                     else {

    private var _avTransportInstanceID = "0"
    
    enum PlayerState {
        case Stopped
        case Playing
        case Paused
        case Unknown
    }
    
    init() {

        }
    }
    
    @objc private func playerButtonTapped(sender: AnyObject) {
        println("player button tapped")
        
        switch _playerState {
