If you’ve already checked that your speakers are on and adjusted the settings for volume control on your computer and the music still isn’t playing, the problem could be the following:
Slideshow does not store your music within the software, but rather a link to the file. In other words if the music is on your desktop when you create the show and then you move it to your music folder, then it won’t play because the link will be incorrect. This issue occurs when you move, rename, or delete a file. If you haven’t deleted the music files, then you can use the wizard to "locate files" and link to the new location. If you want to create a back-up of your show with all associated files then use the "CD/Archive wizard" and this will save photos, video, and music files all in one handy project folder.