What was found
STRONG ODOR LIKE BURNING RUBBER, REPORTED BY F/A AND PAX, ONCE DURING FLIGHT, THEN ON APPROACH AS FLAPS DEPLOYED TO 8 AND 45. ODOR ONLY IN FIRST CLASS CABIN. COULD NOT DUPLICATE BURN LIKE ODOR, RAN LT & RT PACKS WITH APU IAW AMM 21-51-00. NO DEFECTS NOTED. RAN ENGINES IAW AMM 71-00-00 AND ISOLATED, TRYING TO DUPLICATE ALSO, OPS TESTED FLAPS AND SLATS IAW AMM 27-52-00 TO DUPLICATE WRITE UP NO DEFECTS NOTED, COCKPIT AND CABIN ODOR NORMAL. ACFT OK FOR SERVICE AT THIS TIME.