As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, WHEN THE LANDING GEAR WAS RETRACTED, THE FLIGHT CREW HEARD AND FELT A VIBRATION THROUGH THE COCKPIT FLOOR. THE AIRCRAFT RETURNED TO RMS FOR AN UNEVENTFUL LANDING. MAINTENANCE INSPECTED THE AIRCRAFT WHICH REVEALED THE NOSE TIRES OUT OF ROUND. MAINTENANCE PERFORMED A SUCCESSFUL NOSE GEAR SWING IN ACCORDANCE WITH THE MAINTENANCE MANUAL.