As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW INFLIGHT - AIRCRAFT EXPERIENCED PRESSURIZATION PROBLEMS DURING CLIMB AND PASSENGER OXYGEN MASKS DEPLOYED. RETURNED TO DFW AND LANDED WITHOUT INCIDENT. REPLACED ALL PASSENGER OXYGEN MASKS AND OXYGEN GENERATORS REPLACED AS NECESSARY. SYSTEM GROUND CHECKED NORMAL OPERATION.