What was found
RADIO PROBLEMS WHEN FIRST OFFICERS WAFER SWITCH ON RADIO PANEL IS MOVED. THERE IS A STUCK MIC ON WHICHEVER RADIO IS SELECTED. THE FIRST OFFICER HAS A HOT MIC AT ALL TIMES (REGARDLESS OF HOT MIC SELECTOR SWITCH POSITION). CAPTAIN CANNOT TRANSMIT ON EITHER RADIO (USING EITHER YOKE OR TILLER PTT). SUSPECT DRIPPING WATER ON FIRST OFFICER INPH/XMIT SIDE PANEL SWITCH (WINDOW IS LEAKING). REPLACED FIRST OFFICERS PTT/STBY ELEVATOR CONTROL PANEL PERFORMED AN OPERATION TEST FOR CIRCUIT BREAKER LIGHT SWITCH, CO-PILOTS FLIGHT PANEL LIGHTS, INPH/PTT SWITCH AND STANDBY ELEVATOR SWITCH IAW DASH 8 AMM TASK 27-36-11-710-801. CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.