As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT ATTENDANT REPORTED SMOKE IN CABIN, CLOSED TO CEILING. BURNING RUBBER SMELL DETECTED. INSPECTED AND FOUND AFT CABIN ACM FAILED. GROUND RAN AC WITH CABIN ACM OFF FOR 20 MINUTES. NO ODOR OR SMOKE FOUND. OKAY FOR SERVICE. APU COMPARTMENT HAS NO DAMAGE.