As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX - CREW REPORTED WHILE AT CRUISE A PRESSURIZATION WARNING AND UNCOMMANDED DEPRESSURIZATION. EMERGENCY DESCENT TO 10000 FT AND O2 MASKS WERE DEPLOYED MANUALLY. EMERGENCY DECLARED FLIGHT RETURNED LAX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED NUMBER 1 CABIN PRESSURE CONTROLLER. SYSTEM GROUND CHECK NORMAL OPERATION.