Currently, Boombox supports the versioning of both audio files and song lyric files. In order to upload a new version of either file, use the following steps:
Click into the project containing the file you wish to update
Click on the file (audio or text), this will bring you to that file's individual page
On the right side of your screen, click the "upload version" button to call up the upload modal
Upload or drag the new file into the upload modal
Both the new and previous versions of the file should now be accessible via the right side of your screen.