A telephone with a speaker and a microphone uses the speaker both as an electric-to-acoustic transducer, to reproduce the far end partys voice, and an acoustic-to-electric transducer, to capture external sound in the vicinity of the near end party. From the captured sound signal and the signal picked up by the microphone, a decision unit decides whether or not the external sound is being blocked. When the external sound is blocked, a volume control unit increases the volume of the far end partys voice as reproduced by the speaker. The near end party can accordingly turn up the speaker volume by moving the part of the telephone including the speaker close to the users ear to block external sound, without having to manipulate any manual controls.
