As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR - FLT 122 - EN ROUTE JFK-LHR, SEAT 11B HANDSET BECAME STUCK IN HOLDER, ELECTRICAL BURNING HEAT FROM PASSENGER HANDSET BECAME EVIDENT. PASSENGER SEAT POWER WAS TURNED OFF. REPLACED HANDSET 11B. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)