docs: def _notify_media_transport_available(self, path, transport):
          """
          Called by the endpoint when a new media transport is
          available
          """
          self.source = BTAudioSource(dev_path=path)
          self.state = self.source.State
          self.source.add_signal_receiver(self._property_change_event_handler,
                                          BTAudioSource.SIGNAL_PROPERTY_CHANGED,  # noqa
                                          transport)