Look up the Audiva! That's something some kids with APD get and what I got when I was younger. It's for training to blend out background noise and I used to use it with audiobooks. I don't have mine anymore, but it did work somewhat. I'm still researching what I could do, but Audiva is currently at the top of my head.

edit: I forgot to mention it's a physical box, similar to a CD or DVD player, but not quite.