As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATB, ONE HOUR INTO FLIGHT RECEIVED CABIN ALTITUDE WARNING. CREW DONNED MASKS AND RECOVERED CONTROL WITH AUTO 2 SELECTED. NO EMERGENCY DECLARED AND NO PAX MASKS DROPPED. CORRECTIVE ACTION: REPLACED NR 1 AUTO PRESSURE CONTROLLER AND COMPLIED WITH NO-GO TASKS.