Thanks!
ICs are my main suspect here. According to Base PCB layout on IC2L and IC3L positions there should be 74HC595 placed, but I have MM74HC165N/MC74HC165N plugged, and 74HC595 are placed here: IC1 and IC2 (CS PCB)
Can somebody take a look on photos and confirm that this is the case? I would not want to set my sammichSID on fire ;-)
I'm using 12v and 1A adapter - I've checked voltages, no issues.
I have checked all Base and CS PCB voltages - they're all correct (according to my multimeter and chapter 5 of building instruction :))
I have checked these as well - the voltages are correct despite the small scratches (visible on the last photo).
Greets,
Tomasz