As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE AT FL370, ALTITUDE WARNING HORN SOUNDED. PERFORMED EMERGENCY DESCENT TO FL250 AND REGAINED CABIN PRESSURIZATION. AIRCRAFT CONTINUED TO BOS AND LANDED WITHOUT INCIDENT. REPLACED MANUAL PRESSURE CONTROLLER AND PERFORMED LEAK AND PRESSURIZATION CHECK.