As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN ALTITUDE CONTROL JAMMED INFLIGHT. CABIN ALTITUDE EXCEEDED 14,000 FEET. MASKS DEPLOYED. EMERGENCY RETURN TO DFW. FOUND LOOSE HARDWARE OBSTRUCTING MOVEMENT OF OUTFLOW VALVE INDICATOR ON PEDESTAL. REMOVED HARDWARE. RAN BITE OF AUTO PRESSURIZATION CONTROLLERS. BITE CHECKS NORMAL. REPLACING OXYGEN GENERATORS AND MASKS.