I took a different approach and modified the media_player.py code to handle more than 6 zones. I am attaching my modified version for anyone else who may be interested. I would imagine this would need to be replaced each time homeassistant is upgraded but that should be a quick fix.
I have 18 zones across 3 receivers working flawlessly with this.
https://www.netsoft2k.com/Docs/Misc/Homeassistant/russsouns_rnet/media_player.txt
Why don’t you submit an upstream PR? If you don’t have time, I can submit it for you when I get a chance to test it out (if you don’t mind me doing so).
UPDATE: I created a PR add support for mutiple rnet receivers by stonith · Pull Request #96793 · home-assistant/core · GitHub
Hi Richard, really impressed with your solution! Apologies I am total newbie to all this area including Home Assistant. I was using iRule to control my Russound system, iRule is now EOL. So I was looking for another solution and am totally hooked on Home Assistant, offers so much more. In terms of of your solution do you have a step by step guide for dummies on how to set it up? AS mentioned I am only learning how to use Hone Assistant at this stage.
Regards,
Brendan.