As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CRUISE FLIGHT (FL450) CABIN BEGAN TO LOSE PRESSURE. EXECUTED RAPID DESCENT, CABIN BUMPED A COUPLE OF TIMES, CABIN DESCENT STOPPED BRIEFLY, THEN CONTINUED. MANUAL CABIN CONTROL HAD ABSOLUTELY NO EFFECT. R & R THE PRIMARY OUTFLOW VALVE IAW MM 21-32-00. COMPLIED WITH SIMULATED FLIGHT, ENGINES OPERATING FUNCTIONAL CHECKED GOOD IAW MM 21-32-00.