As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 2745 - EWR - CREW REPORTED AT FL 350, SMOOTH AIR QUICK OPEN AND CLOSING SOUNDS COMING FROM NOSE WHEEL DOORS WERE AUDIBLE FROM COCKPIT AND FRONT CABIN. SOUND OCCURRED ABOUT SIX TIMES. EWR MX REMOVED AND REPLACED SOLENOID VALVE. MX PERFORMED LEAK CHECK AND OPERATIONAL CHECK SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.