Musicians And Music Lovers discussion

Does anyone else listen to audio books and background music at the same time?

I have and it changes the mood. I have not found out a way to do it though my ear buds or head phones. I have to play the audio book on one device and play a sound track on another but much lower volume.
For example I listened to The Boy in the Striped Pajamas and in the back ground I played a loop of Adagio for Strings. (The sound track they used for the movie Platoon) It really changes the mood of the novel. I tried it again with some acoustic guitar music and it changed it to a less sad audio book.
I just got Archie Wilson & The Beasts of Loch Ness on audio and stared listening with John Williams CD Theme from Harry Potter. It brings the audio book to life.

Does anyone know how I could combine them so I could hear them together on my phone. Its nice to lay back with your eyes closed and listen, it would be nice if I could do it on the go, on my iPhone, not sure who I could do that. Would I need some sort of mixer to record it?

I tend to have psychical books and background music