Qml Camera live view hangs on Windows Phone

import QtQuick 2.4
import QtQuick.Controls 1.3
import QtQuick.Layouts 1.1
import QtMultimedia 5.4

Item {
    Camera {
        id: camera

        imageCapture {
            id: capture
            onImageCaptured: {
                console.log(preview.toString)
            }
            onImageSaved: {
                console.log(path)
            }
        }
    }

    VideoOutput {
        id: previewWindow
        anchors.fill: parent
        focus : visible 
        source: camera
    }
}