As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3786 CREW DIVERTED TO MSY, FLIGHT ATTENDANT REPORTING PLASTIC BURNING ODOR AND GREY HAZE IN CABIN. NO WARNING MESSAGES OF ANY KIND. AIRCRAFT REMOVED FROM SERVICE. FOUND DUCT UNDER SEAT 7-8BC MELTED FROM NR 2 PACK. REMOVED AND REPLACED SERVICEABLE NR 2 PACK INTAKE DUCT IAW AMM 21-20-05 UNDER SEAT 7-8BC.& 8194; AIRCRAFT RETURNED TO SERVICE.