As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF HEARD A LOUD WHISTLE COMING FROM THE OUTSIDE. ALSO RECEIVED A STALL FAIL CAUTION MESSAGE FOR A FEW SECONDS, THEN IT CLEARED ITSELF. WITH INCREASED SPEED, THE NOISE GOT LOUDER AND FELT SLIGHT VIBRATION. RETURNED TO DEN FOR LANDING. FOUND THE FORWARD NOSE DOOR SERVICE PANEL HAD FORWARD LATCH UNSECURED. RESECURED LATCH, INSPECTED FOR DAMAGE. NO DAMAGE FOUND.