As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENROUTE, WHILE LEVEL AT FL330, THE AIRCRAFT LOST PRESSURIZATION. CREW ACCOMPLISHED A RAPID DESCENT TO 10,000 FT. OXYGEN MASKS DID DEPLOY DURING DESCENT. STANDBY AND MANUAL PRESSURIZATION MODES WERE USED BUT WERE NOT EFFECTIVE. OUTFLOW VALVE WAS REPORTED TO BE FULLY CLOSED. A RUMBLING SOUND WAS HEARD BENEATH THE FLOORBOARDS BY THE FORWARD AND AFT CABIN CREW MEMBERS. FLIGHT DIVERTED AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE ACTION PENDING.