Set MPD output state based on client mute

Before, we simply toggled the output enabled state, assuming that the
mute state changed.

main.py

@@ -39,15 +39,20 @@ async def async_snapcast_client_changed(self, client: snapcast.control.client.Sn
  self._logger.debug('Ignoring change of snapcast client %s: No matching MPD output' % name)
  return
 
+ if output.enabled != client.muted:
+ # If the output is not enabled and the client is muted (or vice
+ # versa), everything is fine.
+ return
+
  self._logger.info('Turning %s MPD output %s' % (
- 'off' if self.mpd_outputs[name].enabled else 'on',
+ 'off' if client.muted else 'on',
  name
  ))
 
  # determine which method to call
- actor = self.mpd.disableoutput if output.enabled else self.mpd.enableoutput
+ actor = self.mpd.disableoutput if client.muted else self.mpd.enableoutput
 
- # invert stored state of the output to avoid calling
+ # fake stored state of the output to avoid calling
  # mpd_output_changed() from mpd_outputs_changed() when MPD notifies us
  # about our own change
  self.mpd_outputs[name].enabled = not self.mpd_outputs[name].enabled