This app worked beautifully at first, but after a few uses the sound I this app stopped working. I tried uninstalling the app and reinstalling, but it still doesn't work. I have the audio on my iPad turned up all the way and all other apps an music work fine on my iPad, so I can't figure out what the problem is here. I try to play the koto strings in this app, and even the pre-programmed music, but there is no sound at all!! And I can't seem to find any support links on this company's website to get assistance here. I need this app so I can practice some koto songs in preparation for a recital soon. Can someone please help me??