A device for reproducing audio with improved convenience by always giving the user a feeling of identify with the user’s action without giving any unnatural feeling such as a discomfort feeling to the user. Music data is stated to be reproduced through a sound signal output section (31) and so forth. The action tempo of the user is detected by a motion information analyzing circuit (23) according to the detection output from a motion information sensor (24). When the difference between the detected action tempo of the user and the tempo of the music data being reproduced is out of a predetermined range, music data of a tempo different from that of the user’s action within the predetermined range is searched for by searching means such as a music reproduction data creating device part (22). A control section (10) changes the music data to be reproduced so that the music data searched for can be reproduced.