As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AN AIR TURNBACK WAS PERFORMED DUE TO CREW REPORTING A LOUD NOISE IN CLIMB FROM THE F/O`S SIDE WINDOW. MX FOUND THAT THE DRAIN TUBE FOR THE R2 WINDOW WAS CAUGHT IN THE WINDOW FRAME. THE DRAIN TUBE WAS ROUTED TO PROPER POSITION AND THE ACFT PRESSURIZED ON GROUND WITH NO FURTHER PROBLEMS.