MP3 Player is very dramatic, as she can be extremely happy, and extremely sad, this is also shown when she spills the beans about Robot Towel and Evil Coin, as she literally starts screaming in embarrassment. She has a vocoded musical voice. She doesn't do well under pressure, as she tries her best to keep her secrets by muting herself in front of Blue Rectangle, little did she realize that it would be easy for Blue Rectangle to unmute her immediately after.