As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORT HIGH SPEED AIRFRAME VIBRATION, IAW TO LOG01 AIRCRAFT VIBRATION. BEGAN TROUBLESHOOTING IAW FELT ON RUDDER PEDALS & REPORTED AS MODERATE IN AFT CABIN. 320 IAW AMM 27-24-00 PG 3 OF 12 UP TO ITEM B, NEED CONT FROM HERE THRU TO END.