Disclosed is a digital audio device that includes a communications port to communicatively connect the device to a server. The device also includes a unique identifier to identify the device. The device also includes a controller to allow transfer of digital audio files from the server. The digital audio files contain interleaved data selected by the server based on the unique identifier. The device also includes a decoder to decode the interleaved data and a data store to store at least one of the digital audio files and the interleaved data.