Dimmer 2 failures since update to 1.8

Hi, I bought a couple of Shellies to try out a few weeks ago, a dimmer 2 and a 2.5, both were working well so I ordered some more.

Now I have a problem, the original Dimmer 2 has stopped working, a couple of lights on off cycles after updating to v1.8.

I tried to factory reset with the switch and removed it and tried with the button. I don't know if it's completely dead because I disabled the led before it died, it's in a home cinema room.

The lamp was 3x60w halogen, wired with no neutral, exactly as the sheet, old Lutron dimmer is back in and working. Shelly Dimmer was tested with a 28w halogen bulb on my desk and nothing working, no sign of life on my wifi or as AP.

I also had another dimmer 2 in a shelly button running a standard lamp (200w halogen) this worked for a only a few minutes, also on V1.8. This one showed the led dimly but also failed to reset by switch or by button or by cycling the power input 5 times. Now the led doesn't light at all.

I emailed the suppliers about replacements already but I'm wary about installing my remaining three Dimmer 2's and haven't updated them past v1.7 they were supplied with. Those three are sitting on the desk running some 30w halogens for testing.

I also have an RGBW2 on master firmware as supplied, led is annoying in the cinema room but it works and I'm a bit concerned about updating that one too.

An update, I was able to recover one of the dimmers with a usb ttl adaptor and the recovery v1.8 image. I found thought that v1.8 wasn't able to connect to my wifi but I was able to update to v1.8.2 in AP mode and now that dimmer seems fine.

The other crashes my USB adaptor when it's connected so I think that one has really failed.