now a working radio controller

HOWTO.md

@@ -506,6 +506,7 @@ events:
 
 Volume actions are also available as `denon.volume_up` and
 `denon.volume_down`. Each call sends five volume steps to the receiver.
+`denon.volume_mute` explicitly mutes the main output.
 
 The Denon receiver connection is also configured in `events.yaml`. Power
 actions use Denon's HTTP control endpoint; set **Settings → Network → Network
@@ -534,4 +535,27 @@ After changing `events.yaml`, restart the listener:
 ```bash
 sudo systemctl restart zigbee-events.service
 ```
+
+### HEOS favorite stations
+
+The receiver's HEOS Favorites can be discovered and played through its CLI
+service on port 1255. The library resolves the player and Favorites source IDs
+dynamically:
+
+```bash
+python3 lib_heos.py list
+python3 lib_heos.py play 1
+python3 lib_heos.py play "NPO Radio 2"
+```
+
+Favorite numbers are the current 1-based positions shown by `list`. Names are
+matched case-insensitively. Playing a favorite starts playback on the first
+HEOS player returned by the receiver.
+
+`denon.next` checks the AVR power state before changing stations. In standby it
+starts favorite 1. When powered on, it advances only if the current station is
+in HEOS Favorites, wrapping the final favorite back to the first. It does
+nothing when another source or a non-favorite station is playing.
+`denon.previous` has the same rules in reverse and wraps favorite 1 back to the
+final favorite.
 - [RRDtool graph elements](https://oss.oetiker.ch/rrdtool/doc/rrdgraph_graph.en.html)