As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DEPARTURE CABIN PRESSURIZED TO APRROX 5000' TO 6000' BELOW SEA LEVEL, AND SHORTLY AFTER STABILIZING, DURING CLIMB CABIN WAS CLIMBING AND DESCENDING GREATER THAN 2000FPM, PRESSURIZATION ERRATIC. CORRECTIVE ACTION: REMOVED AND REPLACED RIGHT OUTFLOW VALVE PER M/M21-34-51 OPS CHECK NORMAL.