We accept mp3 or WAV files at any sample size and bitrate. However, they must be in stereo or they will not be accepted by the stores. 

If you need to convert your music to the correct format, the simplest way is to use iTunes. 

- Launch your audio file in iTunes. 

- Select 'preferences' in the top menu, followed by 'import settings'. 

- Change this to ‘WAV Encoder' and the following settings: 16 bit (sample size), 44.1 kHz (sample rate), 1411 kbps (bit rate).

This will convert your files to the best format.