A microphone is arranged on the first surface of a first housing, which opposes a second housing in a close state. A first speaker is arranged on the second surface of the second housing, which opposes the first surface in the close state. A second speaker is arranged on that surface of the first or second housing, which is exposed to the outside in the close state. A detector detects whether the first and second housings are in the close state. When communication is being executed, the state of the first speaker when the first and second housings are not in the close state is a valid state, and the close state is detected by the detector, a control section invalidates both the microphone and the first speaker and validates the second speaker.