Hello,
in these days I tried everything.
I set Trailing edge. I repeated calibration a lot of times.
I downgraded firmware to 1.9.0. I upgraded to beta firmware 1.10.2.
But the result is always exactly the same.
After a while with lights on at 100%, the "shelly dimmer 2" with 9 leds (~70W load) becomes hotter and hotter, and when its temperature raises to ~105°C it switches off with overtemperature error.
First time it happens after about 10-15 minutes of activity. Then, if I switch it on again when it's still quite hot, it lasts less.
No problem with the other "dimmer 2" with 6 leds (~43W load): it becomes a bit hot (about 95°C) but then it keeps stable.
As stated before, I tried swapping them, so it's not a matter of a defective unit.
I don't understand why the shelly dimmers become so hot.
My previous simple shelly 1's never gave me problems.
If I keep open the electric box where the shellys are installed, the dimmer with 9 leds does not become so much hot, and it seems stable. However for obvious reasons I cannot keep it open.
I'm sad... If I don't find a solution soon, I think I'll have to return the shellies...