As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2492 - THE CREW REPORTED DURING CRUISE THAT THE NUMBER TWO RMU FAILED, WITH NO TRANSPONDER AND RADIO STUCK. THE AIRCRAFT RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED THE AIRCRAFT AND REMOVED AND REPLACED THE NUMBER TWO INTEGRATED COMM/TRANSPONDER UNIT, OPERATIONALLY TESTED ALL RADIOS AND TRANSPONDER WITH NO DEFECTS, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.