Sonoff T1 3 gang V.1.0 not connecting to Deco wifi

Seeking advice from electronics experts.

I have flashed the first gen Sonoff T1 3 gang R2 V.1.0 board with tasmonta. All good!

Added to my wifi (deco) and home assistant whilst connected via usb to my computer - all good!

Put the thing back together, wired it up, and it would no longer connect to my wifi - not good!

Problem solving led me to this photo you see below which again connected to my wifi.

Worth noting that the V.1.1 boards do not have the same problem as I have some of these as well. and tested it with them.

Makes me think that the a/c voltage side of the main switch is causing some sort of interference with the low voltage board and wifi…?

Any ideas on how to fix this? I also flashed with esphome but same problem…

(Note it is the v1.0 board which has all the chips on the inside of the board. From V1.1 and up they are on the outside).

I don’t think my wife will allow switch’s hanging out of the wall like this…

Did you correctly configure the module in tasmota? Also try without the motion switches. Check if then its connecting?

Yep, it is not a tasmota issue. As mentioned I also did the same thing with esphome.

It connects to the wifi when the circuit board is not in proximity to the mains board.

That actually shouldn’t be a factor. Its strange. Did you check if the touch switches and relays are woriking even when the device is not connected to wifi? I am asking because in normal conditions esp devices wont boot if some gpio pins are either pulled high or low during boot. It there is some issue with the connecters of the main board and the front panel board, this could happen.

Yep. All functioning normally when not connected to wifi.
Also, I have another router, tested it with that and it connected.
I also have a two gang, but with a v1.1 board. I connected the three gang v1.0 to the 2 gang v1.1 mains board and it connected.
So it is a Deco router issue but only with the v1.0, and only when the device is assembled to the three gang ac board.