As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3572 THE CREW REPORTED THAT SHORTLY AFTER TAKEOFF THE MASTER WARNING WENT OFF AND THEY RECEIVED A RED "BLD 2 LEAK" EICAS MESSAGE. AN ASSOCIATED CONDITION: RADIOS BECAME SCRATCHY AND UNREADABLE. THE CREW DECLARED AN EMERGENCY AND ELECTED TO RETURN TO SDF. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE "O" RINGS AT BLEED SYSTEM 2 JOINT 18 IAW AMM CH 36-11-10. NO LEAKS NOTED. THE AIRCRAFT WAS RETURNED TO SERVICE.