I have purchased 2 of this :https://www.hobbyking.com/hobbyking/store/__78696__Turnigy_9X_Replacement_Mother_Board.html
But after replacing it, the buzzer start to buzz when I connect the battery to the socket,without activating On/Off switch.
It stop buzzing when On/Off switch is put to On.
This happen with both main board.
Does bouth main board have an error?
Any out there with an answer?