As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RTO AT CVG MAXIMUM ATTAINED AIRSPEED 5 KIAS. UPON INITIATION OF TO THRUST, THE TO WARNING HORN SOUNDED. AFTER TAXIING CLEAR OF THE RUNWAY, NOTIFIED FLIGHT CONTROL AND ADVISED THEM OF THE PROBLEM. MX CONTROL HAD BEEN NOTIFIED PRIOR TO CALLING FC. AFTER WE MOVED THE SPEED BRAKE HANDLE IN & OUT OF DETENT SEVERAL TIMES THE PROBLEM APPEARED TO BE SOLVED. THE REMAINDER OF THE FLIGHT WAS UNEVENTFUL.