Use an MP3 player shield (example: http://shop.boxtec.ch/player-shield-p-40699.html), it includes the necessary hardware to produce sound. You may have to add an amplifier but they are cheap in the phone accessory market.
Use an MP3 player shield (example: http://shop.boxtec.ch/player-shield-p-40699.html), it includes the necessary hardware to produce sound. You may have to add an amplifier but they are cheap in the phone accessory market.