Hello there!
I configured a Yamaha MusicCast sound bar to use it with HomeKit (power on, play radio, change HDMI channel, etc.) and it works pretty good except for one particular case.
This soundbar (like other devices) are connected to z-wave managed plugs that are powered off to save power during the day.
This is where my problem comes up, if for any reason my home-assistant services are restarted when my MusicCast is not powered on (completely disconnected from power), the entity is removed from config and do not come back when my Yamaha is powered on. The only way to bring it back is to power it on and restart home-assistant services, which is not very handy…
Maybe I missed something in the configuration or should I do it differently… here is my configuration:
media_player:
- platform: yamaha_musiccast
name: Receiver
host: 172.16.1.107
Any help is welcome 
Miguel