As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN DIFF VVI CONSTANT +300-400 DURING FLT CAB AH AND DIFF PSI REMAINED STEADY 7000 FT AND 7.6 PSI AT 350 FL. GROUNDED - YES. REMOVED AND REPLACED RATE OF CLIMB INDICATOR REF AMM 21-33-01 OPS CHECK GOOD, NO DEFECTS NOTED REF FIM TASK 21-61-00-740-8041-002.