As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN RATE OF CLIMB INDICATOR FLUCTUATES +- 300 FPM IN FLIGHT AT VARIOUS CRUISE ALTITUDES. COCKPIT "AIRFLOW" NOISE FLUCTUATES AT SAME TIME. ACFT GROUNDED. PERFORMED FIM 21-31, TASK 801, DCPC BITE ON BOTH CONTROLLERS. NR 1 AND NR 2 DCPC TEST OK WITH NO EXISTING FAULTS. NR 1 DCPC LOGGED OFV LRU FAIL ON PREVIOUS FLIGHT. FAIL WAS CODE 011. PERFORMED FIM 21-31, TASK 802. REPLACED OUTFLOW VALVE, TESTS CHECKED OK, REF MM 21-31-03.