[WMF] Unable to show video preview (first frame)

import QtQuick
import QtMultimedia

Window {
    width: 640
    height: 480
    visible: true

    VideoOutput {
        id: vo
        anchors.fill: parent

        MediaPlayer {
            id: mp
            videoOutput: vo
            source: 'qrc:///sample_640x360.mp4'
            Component.onCompleted: {
                // play/pause trick to display first frame
                play()
                pause()
            }
        }

        TapHandler {
            onTapped: mp.play()
        }
    }
}