As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CRUISING AT FL340 NOTICED ALT PRESS CLIMBING SLOWLY AND INCREASING IN RATE. PERFORMED EMERGENCY CAB ALT HI QRC EICAS MESSAGE CAB ALT HI AND MANUALLY CHANGED CABIN PRESS AYT FL 100 AND BELOW. DECLARED EMERGENCY, DIVERTED TO LIT, LANDED WITHOUT INCIDENT. R&R CPCS CONTROLLER AND OUTFLOW VALVE ACTUATOR, OPS CHECK GOOD. ALSO REPLACED OUTFLOW VALVE ACTUATOR P/N 21598-01 S/N 1070 TSN 21526 CSN 13373.