As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS AFTER GATE ARRIVAL COULD FEEL VIBRATION IN FORWARD GALLEY FLOOR. STARTED GETTING SMOKE, TURNED BLOWER AND EXTRACT OFF, TURNED APU OFF AND VIBRATION STOPPED. MAINTENANCE REPLACED AVIONICS EXTRACTION FAN IAW AMM 21-26-51-400-001-A.