As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR RETURN DUE TO THE PILOT SUSPECTING THE NR 4 SPOILER ACTUATOR WAS FLUTERING. IAW TSM 27-60-00-810-846-A FAULT WAS COMFIRMATION. R & R THE NR 2 SEC IAW AMM 27-64-51. REMOVED AND REPLACED SPOILER SERVO CONTROL 31CE9 IAW AMM 27-64-51, OPS AND LEAK CHECKED GOOD. AIRCRAFT IS GOOD FOR CONTINUE SERVICE.