let me know how you go... ALL of the pins in the connector (except pin 29.. key pin should have a wire going to it). If the plugs are mixed up on the sound board end it can put a short across the 5v line. Also it might be worth checking between pin 30 and ground with an ohm meter on the soundboard incase its shorted.. could be a shorted cap C1, or a shorted logic chip U1 to U6.
