@Odin Great, glad it's working. PSU was on my list as one of the next things to investigate! Though your M122 report showed 12V working fine.
Supply voltage: min 12.1, current 12.1, max 12.2, under voltage events: 0, over voltage events: 0, power good: yes
Might be worth changing to 24V if the motors are bigger. Also, it's best to use ferrules on the ends of your VIN wires, for better contact and hold in the screw gates, rather than just bare wires.
Ian