Interesting. some more info please :-)?
On the firmware of on the relay?
The reason why I want a relay is to be able to use my KAKU doorbell. By doing so it will allow me to still use my KAKU signal inside homeassistant (RFXcom needed!).
More info (in Dutch): https://community.athom.com/t/ezviz-db1-deurbel-met-homey-werkend-via-trucje-icm-kaku-zender/33811
Warning - 300+ page thread. Page 101 is the overview/quick-start from months ago. Read it first, then head on to page 300+ for the latest news.