What was found
AT FL340, 112 MILES FROM MSY, FLIGHT ATTENDANT COMPLAINED OF PLASTIC BURNING SMELL ROWS 5 - 7DEF. ALSO, HEARD CRACKLING SOUND WITHIN 3 MINUTES. INITIATED DESCENT & DECLARED EMERGENCY. DIVERTING TO MSY, OVERHEAD BINS CHECKED, NO HEAT DISCOVERED. COMPLIED WITH CABIN ODOR JOB CARDS 26L00021001 & 26L00021005. FOUND FAULT WITH AEVC OUTLET BYPASS VLV 23HQ. REPLACED VLV IAW AMM 21-26-55-400-003-A. OPERATIONS TESTED GOOD. NO CABIN ODOR AT THIS TIME.