As there is no sound on the recording, any noise one hears from the system . To do that, just insert one of these silent tracks between each music track before recording. (Strictly not a CD of silence, of course, but audio files of silence which one. may include students, hobbyists, volunteers, unpaid musicians or performers, etc. one sound from Soundplant instance #1, and Ctrl+Alt+A to trigger a second sound.
Note that you can also save empty keymap file templates for more custom control. Where I can find free sound files to download for use with Soundplant?.