As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOTS WROTE UP A RUMBLING SOUND WHEN CHANGING TEMPERATURES IN THE COCKPIT. ON INVESTIGATION THE CONDITIONED AIR HOSE THAT RUNS UNDER THE PILOTS FLOOR NEXT TO THE ELEVATOR CONTROL ROD AND BELLCRANK WAS FOUND RUPTURED. THE PLASTIC WINDING THAT HOLDS THE HOSE SHAPE UNRAVELED. THE HOSE WAS REPLACED.