What was found
INFLIGHT, BOTH LEFT AND RIGHT COMMS FAILED TO TRANSMIT, COULD RECEIVE. EMERGENCY DECLARED. R & R THE FIRST OFFICER'S PTT YOKE SWITCH WHICH WAS FOUND STUCK AND CAPTAIN'S AUDIO PANEL, ALSO R & R THE AUDIO ACCESORY UNIT, ALL OPS CHECKED GOOD IAW AMM 23-12-02, AND WDM 23-51-21.