I’ve had this happen once before.
The controller sends current through the terminals even in the off position. On a previous job I installed 3 Hunter controllers on a unit complex in Balga only to discover all 3 were constantly sending current through the terminals meaning valves were staying open.
After numerous attempts at re-wiring and trying to locate the problem in the solenoids I ended up changing the controllers out and all was well again.
This one was from a job I did yesterday. Onsite various terminals would send power at odd times and after half an hour of fiddling I decided it was quicker to change the box over than to persist with seeking a solution.
I don’t get many faulty X Cores, but this one is going back…