1. A vehicle having a function to allow a user to talk on a mobile phone, comprising: a microphone for receiving sound to be transmitted to a far-end user, and loudspeakers for outputting sound received from said far-end user, wherein means for outputting a test sound through each of said loudspeakers; means for detecting a sound pressure level of said test sound from each of said loudspeakers; and means for selecting, on the basis of said sound pressure level, one of said loudspeakers as a loudspeaker for outputting sound received from said far-end user.