[ZOA NOM]

Symptoms definitely can be caused by cold or cracked solder joints. Difficult to see, but can interrupt signal. I would check and re-solder any joints that look suspect. You can even wholesale reheat each connection (time consuming) to refresh the continuity. You should be confident in your soldering skills before doing this, and it requires no new solder, just re-heating the joint until the solder turns liquid and re-hardens. I would confirm the integrity and continuity of all wiring first.