What was found
(CAN) CREW REPORTED A VERY STRONG ACRID ODOR AROUND SEAT 11A. QRH WAS CARRIED OUT AND A PHONE PATCH WITH MAINTENANCE CONTROL WAS ESTABLISHED. POWER WAS DISCONNECTED FROM THE AREA AND THE ODOR DISSIPATED. THE CREW INCREASED SPEED AND ELECTED TO DECLARE A PAN PAN TO ENSURE PRIORITY HANDLING INTO STA. QSEB IN THE MONUMENT BEHIND SEAT 11A FAILED WITH VISIBLE EVIDENCE OF COMPONENT OVERHEAT FAILURE. BOTH QSEB`S REPLACED IAW AMM 44-22-78, DOWNLOAD TO QSEB 11A OK, DOWNLOAD TO QSEB 18AB, NO JOY, MISMATCH, DEF DUE TIME. 18AB QSEB DOWNLOAD & IP SEQUENCE CARRIED OUT OK.