SHELLY firmware BUG

[richard-g8jvm (Richard Bown)]

If your shelly device works DO NOT update the firmware
I’ve found this on both the Shelly1 and the Shelly EM
controlling the relay on both types now no longer works.
It doesn’t matter what settings you use in the http gui, the switch button on the gui takes priority
You can change the state of the relay via mqtt, but within 20seconds it will revert back to what ever the state of the button on the web gui, their embedded firmware, is set at.

So now I have four un-useable Shelly1 switches and a Shelly EM that cant control a contactor or external relay.

[mauroreggio (Mauro)]

Hi richard.
I know that this post is a little bit old, but i run into this in the past 2 days.
My workaround was downgrade my shelly device firmware at an old version.
After this all works fine with my HomeAssistant (now at 2020.12.1 version).
In details:

• from this link i found info about how downgrade shelly firmware: https://sequr.be/blog/2020/11/home-automation-force-update/downgrade-shelly-firmware/
• This website (that you can find in the previous link) can give you a link to paste into your browser for make your shelly device download and install an archived old firmware: http://archive.shelly-tools.de/
  In my experience, downgrade to Shelly Firmware version 1.7.0 make my integration works again.
  Hope is usefull.
  Bye.
  Mauro.