As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MODERATELY STRONG BURNING RUBBER ODOR IN COCKPIT, 30 MINUTES AFTER BLOCK OUT. COFFEEMAKER TURNED OFF. ODOR RETURNED APPROX 15 MINUTES LATER. NO SMOKE. COMPLIED WITH INSPECTION OF COCKPIT, AFT EQUIPMENT BAY, & AVIONICS BAY. NO DEFECTS NOTED. COMPLIED WITH MINIMUM WORKSCOPE FOR SMOKE/FUMES IN CABIN/FLIGHT DECK. UNABLE TO DUPLICATE DISCREPANCY.