The possibility of renaming the USB files (with more than 8 characters), and classifying them in a directory?
A small MP3 player for the background sound would be a plus.
Basic MP3 playback would be very handy for house music
@Carl N
What is wrong with using wav files ?
Cant you playback mp3 from an iphone or ipad like device using a stereo input?
You might need an adaptor but still not a hard way to do it without needing changes to the SQ.