An operation section housing and a display section housing are connected by a rotatable hinge having a structure in which the display section housing rotates with the rotatable hinge serving as the central rotational axis. The display section housing has three built-in speakers in predetermined positions of a display. A personal digital assistant detects the angle of the rotatable hinge and identifies the speaker located in the leftmost side and the speaker located in the rightmost side relative to an upright display image displayed on the display. Then, the left audio is output from the left side of the upright display image and the right audio is output from the right side of the upright display image.