As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED A BURNING ODOR IN FLIGHT, SULFUR BURNING ODOR. THE ACFT LANDED WITHOUT INCIDENT WHERE MAINTENANCE INSPECTED THE ACFT MAINTENANCE R & R THE NR 1 ACM, OPS TESTED WITH NO DEFECTS. THE ACFT WAS APPROVED FOR RETURN TO SERVICE.