As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
COCKPIT ODOR BURNING SMELL - ENROUTE WE SMELLED A FUEL/OIL BURNING SMELL IN THE COCKPIT. THAT WOULD COME AND GO EVERY FEW MINUTES. AFTER LANDING THE SMELL WAS NOTICEABLE IN THE AFT EQUIPMENT BAY. NOTE, WE DID NOT GET DEICED AND THE APU WAS RUNNING ON THE GROUND BUT NOT IN THE AIR.