Starscream: Error: Invalid HTTP upgrade

Hi,

I have random connection problem which display these logs:

websocket is connected
websocket is disconnected: "Invalid HTTP upgrade"

code:

    let useSSL = true
    let websocketScheme = "wss"
    let host = "x.x.x.x"
    let port: NSNumber = 8080

    public init() {
        let components = NSURLComponents()
        components.scheme = websocketScheme
        components.host = host
        components.port = port
        components.path = "/"

        webSocket = WebSocket(url: components.URL!)
        webSocket?.selfSignedSSL = useSSL
        webSocket?.delegate = self
        webSocket?.connect()
    }

It happens on iOS 9.0.1 (iPads). With swift 1.x and Xcode 6.x everything worked well, but now it randomly failed. Please give me some suggestion. Thank you.