I need a simple tool that will allow users to slow down playback of mp3's and wav files. The pitch should not change. I'd like for users to be able to pick a start and stop point and loop playback so that they can figure out how to play instruments in different songs. You can get a better idea of what I'm looking at here (free demos available): [url removed, login to view] I don't really need all the features of the souped up version. This will be a freebie given away to incentivise purchase of another product. Looking for recommendations on programming language.