The expiration of a validity period of song data for each of a plurality of songs is determined by comparing validity period data of the song data, which are stored in a song data storage area 20a for storing the song data including the validity period data, with the current time and date shown on a timer 30, and expired song data are deleted. Further, song data which do not exist in the song data storage area 20a are identified by comparing the storage content of the song data storage area 20a with a data list transmitted from a server 80, and a request is placed with the server 80 for distribution of these song data.