As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, NOTICED LOUD SUSTAINED VIBRATION IN CABIN FROM LEADING EDGE OF WING AFT INTO MID CABIN AREA. ALSO, FELT IN FLOOR OF COCKPIT. VIBRATION REMAINS AT ALL POWER SETTINGS. AIRCRAFT RETURNED TO FIELD. *S/D* ADJUSTED NR 7 SLAT PER AMM 27-81-00.