All my sonoff mini broke

Hi
Once, all my sonoff mini switches got damaged at the same time and all of them have the same problem: burned out fuse resistor. But everything else works properly. Does anyone have any ideas about the reason, what might have happen?

Possibilities:

  • Not designed for the environment they were installed in. What is the average temperature where they are installed?

  • Not designed to withstand prolonged over-voltage. How stable is your power?

They are located in my house, I thought about over-voltage but I’m embarrassed that the rest of the devices were not affected. I guess, my electricity more often has low-voltage than over, because I live in a countryside

Temperature?

All of my minis are dead after a thunder storm. Looks like they were fried by a power surge likely caused by lightning.