As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREFLIGHT INSPECTION FOR FLIGHT 4445 THE FLIGHT ATTENDANT REPORTED A BURNING SMELL IN THE CABIN. AIRCRAFT REMOVED FROM SERVICE. PACKS, BALLASTS AND RECIRCULATION FANS WERE ALL CHECKED AND NO SMELL WAS FOUND. AIRCRAFT RETURNED TO SERVICE.