A system for interfacing with an audio player comprises a housing (110, 410) containing a first connector (111, 411), a transmission device (120, 420) including a second connector (121, 421) capable of removable engagement with the first connector, a power interface (130, 430) electrically coupled to the housing, and an audio interface (140, 440) electrically coupled to the housing and capable of being coupled to the audio player. The transmission device is connectable both to the housing and to the audio player directly, and is capable of transmitting an audio signal generated by the audio player to a playback device such as a radio.