Hi Nobby,
I don't think you will be able to put one of my MP3 files on a floppy disk because they are all larger than the typical 1.44 Mb a floppy disk can store; maybe I could record a song which is less than 1.44 Mb, but it would last only a minute or so... and I am afraid that you cannot hear an MP3 file on your keyboard because it does not trasmit data of any kind, like a midi file does, so you can just store it on your hard disk and play it through your computer speaker system.
Hope you are not disappointed...
How's going on in Missouri?