As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INTERMITTENT BURNING RUBBER/PLASTIC ODOR IN MID CABIN DURING CRUISE. ODOR CENTERED AT ROW 17 CAME FROM AIR VENTS. STRONGER ON LEFT SIDE OF CABIN BARELY NOTICEABLE ON RIGHT SIDE. TURNED GASPER FAN OFF ODOR DISSIPATED. NOTIFIED ATL MTC ACARS 1825Z. RAN RECIRC FANS AND GASPER CANNOT DUPLICATE ODOR. NO ODOR NOTICED.