As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCI - FLT 337 - UPON LEVEL OFF AT FL350, CABIN CONTINUED TO CLIMB. DESCENDED TO FL240. CABIN ALTITUDE REACHED 13000 FT. REGAINED CONTROL OF CABIN WITH MANUAL CONTROL OF OUTFLOW VALVE. REPLACED BOTH CABIN PRESSUE CONTROLLERS AND BROKEN CLAMP ON A DUCT. (M)