As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DOOR 1R HAS LOUD SQUEEL A/C PRESSURIZATION NORMAL AT FL350 BUT AIR RETURN FOR LOUDNOISE FOUND CART SEAL IN DOOR SEAL. REMOVED CART SEAL AND INSPECTED DOOR FOUND NO OTHER ISSUES. PERFORMED PRESSIZATION CHECK, NO LEAKS NOTE. REF : TASK 21-31-00-710-801