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Due to hardware constraints on the board, you won't be able to play compressed music formats such as MP3. The file will need to be in a specific uncompressed file format, which can be fed directly to the playback hardware that is on the board.

A consequence of this is that the uncompressed sound streams will be much larger, so only short audio clips will be able to be stored on the device. This still opens up a number of possibilities for playing sound effects or other short audio clips.