Another bug: had broken the business of remembering the volume on sleep and shutdown. This seems to improve it, but now I'm unsure of the logic ... what should happen if the app is put to sleep and the volume is changed, and then the app wakes up again?
To do this with any generality, will have to dispense with the pre-built MIDI files. It should be possible to generate those, put them in a cache, then read them in when needed.
FIxed a bad bug with yesterday's commit, which was meant to allow simultaneous playing of notes (not strumming yet).
Can now play multiple notes simultaneously, but not by "strumming" per se, but by hitting one button after another.
Made possible to play multiple notes. Still can't strum, exactly.
Corrected first string of Ukulele, added missing MIDI files.