As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THREE MINS AFTER TAKEOFF, THE COPILOT NOTED A SPLIT IN TORQUE SHOWING THE #1 ENGINE HAD ROLLED BACK TO 40% TORQUE. THE ENGINE WAS BEEPED UP AND THE AIRCRAFT WAS RETURNED TO BASE. TROUBLESHOOTING FOUND NO DEFECTS NOTED. FOR PRECAUTIONARY MEASURES, REPLACED #1 ENGINE N2 ACTUATOR AND N2 CONTROL BOX.