Thanks for your suggestion but I’ve tried all that. The Casio Music Space app has a function called Music Player, which allows you to “Play along with your favorite songs.” Songs have been preloaded into the app but they all sound like ringtones. They’re not really songs. The app’s Functions Chart shows that mp3 files are supported, but I don’t understand how to upload mp3 files into the app. Besides, I’m not really interested in playing along with music on mp3 files. I want to pipe music from YouTube into the keyboard and play along with that while listening with headphones.