As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB NOTICED CABIN ALTITUDE CLIMBING ABNORMALLY HIGH. RECEIVED CABIN ALT CAUTION MSG. FOLLOWED BY CABIN ALT WARNING. CW IAC AND QRH CMSGS CLEARED IN DECENT. AIRCRAFT REMOVED FROM SERVICE. INSPECTED AND FOUND OVB EXHAUST SOV NOT FULLY CLOSED. SET TO THE CLOSE POSITION REF 367692-4 FOR MEL, VERIFIED CB WERE PULLED AND COLLARED. NO OTHER DEFECTS NOTED AT THIS TIME. REMOVED AND REPLACED INBOARD EXHAUST VALVE IAW AMM 21-24-31. OPS TEST GOOD REMOVED PLACARD AND REMOVED FROM MEL.