As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APPROXIMATELY 15 MINUTES INTO THE FLIGHT, HEARD A RUMBLING NOISE WHILE CLIMBING TO FL320. PRIOR TO REACHING THE FLT ENGINEER COULD NOT CONTROL THE CABIN, INITIALLY THE CABIN WAS AT 5500 FEET APPROACHING FL260. IT SHOULD HAVE BEEN AROUND 4400 FEET AT FL 260. STOPPED THE CLIMB AT FL260 BUT THE CABIN CONTINUED TO CLIMB, AND WORKED THROUGH THE CHECKLIST. DECENDED AND IT TOOK 10000 FEET TO STABILIZE THE CABIN. RETURNED TO DEPARTURE.