As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT, THE MAIN CABIN DOOR HAS LOUD HISSING NOISE. LOUDEST AT FORWARD LOWER AREA OF DOOR SEAL. REMOVED SEAL P/N 9914195-4 5/N UNKNOWN. CLEANED AND PREPPED SURFACE WHERE THE SEAL SITS. INSTALLED CUSTOMER SUPPLIED NEW SEAL P/N 9914195-4 S/N 1151. OPS CHECK AND LEAK CHECK ARE ALL GOOD. ALL WORK DONE IN REF TO AMM 52-10-04,