As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 2 ENGINE AURAL FIRE WARNING AT TOP OF DESCENT NO VISUAL ALERT TESTED FIRE WARNING RECEIVED. VISUAL WHEN TEST FINISHED. SHUTDOWN NR 2 ENGINE IAW PROCEDURES FIRED BOTH BOTTLES. DID NOT EXTINGUISH ALERT. FCDU REMOVED. FAULTY REMOVED AND REPLACED FCDU.