As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED ON CLIMB THE CABIN RATE OF PRESSURE CONTINUED TO RISE BEYOND NORMAL. THE FLOW LIGHT CAME ON AND THE OUTFLOW VALVE FULLY CLOSED AND THEN THE CABIN RATE OF CLIMB RETURNED TO NORMAL. FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED AIR PRESSURE REGULATOR. SYSTEM GROUND CHECKED NORMAL OPERATION.