I haven't been able to try this out personally but just read a wonderful review on this app, and the idea is brilliant! I work with many kids with Apraxia/Motor Planning difficulties and they often LOVE music but they are unable to sing along with the fast-paced songs. Here is an app that you can download on your iPhone or iPod and add your songs and it will SLOW down the music with supposedly no degradation to the quality of the music! What a fabulous idea! I often sing songs very slowly with these kiddos so they can start to follow along with the songs when they are on CD, and it always bugged me that kids songs on CD's are always SO fast paced. Music can really help develop language, so hopefully this might help a lot! Please check it out, and if you do, let me know how it works and how your little one responds!
https://itunes.apple.com/us/app/slowtunes/id657117134?mt=8
https://itunes.apple.com/us/app/slowtunes/id657117134?mt=8