def set_mute(self, enable):
        """Mute or unmute the TV."""
        data = '1' if enable else '0'
        params = ('<InstanceID>0</InstanceID><Channel>Master</Channel>'
                  '<DesiredMute>{}</DesiredMute>').format(data)
        self.soap_request(URL_CONTROL_DMR, URN_RENDERING_CONTROL,
                          'SetMute', params)
Mute or unmute the TV.