As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 622 - LAS - BURNING SMELL - ON TAKEOFF WITH FLEX POWER SET, CREW NOTICED AN ACRID BURNING SMELL WITH LIGHT HAZE OF SMOKE. AFTER LIFT OFF, A LOW GRINDING NOISE WAS ALSO NOTICED UNTIL AFTER FLAP RETRACTION WHICH RETURNED FOR A SHORT TIME ON DESCENT. MAINTENANCE REMOVED AND REPLACED THE NR 1 AIR CYCLE MACHINE IAW AIRBUS MAINTENANCE MANUAL 21-52-21.