Only thought may be, as you are soon to go hooking it up to your wrist (yes through a 1M resistor, but it can still fry logic) call in a sparky to do a polarity check of the houses outlets, that earth is earth and your phase and nuetral are not inverted,
As stupid as it seems, i can recount 4/13 outlets at my hourse, 2/22 at a neighbours and a number more that did not just have active and phase reversed, but one had active and ground reversed, nothing worked in that outlet, so people avoided it, but you can see the issue,