As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DIRTY SOCK SMELL IN FRONT GALLEY AREA, ESPECIALLY BY DOOR 1L. DURING TAKEOFF, ODOR DISSIPATED VERY SLOWLY. MAINTENANCE FOUND FORWARD LEFT HAND AND RIGHT HAND DOOR SILL DRAIN LINES AND FUSELAGE CHECK VALVE BLOCKED. MAINTENANCE ALSO REMOVED CLEANED AFFECTED LINES AND VALVE.