If your child likes music, this is a great way to avoid the repetition that will drive you crazy. Get a CD player that will play MP3 files. Get all your child’s favorite CD’s and rip the music files off them. Then burn a single data CD with all those songs on it, you’ probably be able to get up to 100 songs on there. Now, put that into their CD player and put it on shuffle. You should be able to get up to 5 hours of non-repeated music out of this.
To get an even better music library, try making up a disk for sleepy music, playtime music, party music and others. Use a printer to print CD labels on them and then you can decorate each one with the right look.