kivy 1.8 playing ogg

gistfile1.txt

def play(sound_fname, loop=False):
    if sound_fname is None:
        return
    sound = SoundLoader.load(sound_fname)
    sound.loop = loop
    if sound:
        sound.play()
    return sound

new_sound_fname = 'audio/back_menu.ogg'
play(new_sound_fname, loop=True)


--- running with Kivy 1.8.0 I see these errors:

DEB: Starting background sound: audio/back_menu.ogg
[WARNING           ] [AudioGstplayer] No decoder available for type 'audio/ogg'.
[ERROR             ] [AudioGstplayer] Your GStreamer installation is missing a plug-in.
[ERROR             ] [AudioGstplayer] A Ogg demuxer plugin is required to play this stream, but not installed.
[ERROR             ] [AudioGstplayer] GStreamer encountered a general stream error.