To provide an in-car audio system capable of transferring and preserving data in units of contents when the data transferred from a home PC is interrupted.

The in-car audio system stores the data received from the home PC with a communication means in a storage means, and interrupts storage of the data in the storage means in units of contents when a sign of engine starting is detected in the middle of receiving the data to hold a communication status with an external electronic apparatus by the communication means for a predetermined period of time. Then, data transfer of a following content is restarted if an engine does not start within the predetermined period of time. If the engine starts, the communication is interrupted.