As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INSPECTION TYPE:N/A**ATB**BOTH RADIOS TREMENDOUS SQUEAL BOTH AUDIO PANELS SWITCHED TO ALT FOR REMAINING OF FLT SQUEAL STARTED AT APPLICATION OF T/O POWERR/R OBSERVERS POSITION AUDIO SELECT PANEL PER AMM 23-51-01-404-014. NO FAULTS NOTED. THIS CLEARS M796611