A potential freeze bug has been discovered on multitasking devices (basically iPhones or iPods running 4.0 or later). If you quit the app while in the settings or help screens, the app looses response when you restart it. A bug fix has been uploaded to iTunes and should be out soon. In the meanwhile, if you get the error – just doubleclick the home button and force quit The Mouth Harp. When it reloads it should be working again.