While obviously a fail on the part of the publisher, this can be fixed. The back side needs to be made opaque, which can be done numerous way… sharpie, enamel paint, or for something less permanent you can still buy CD labels which are vinyl or paper sheets die cut to the size of a CD and coated with an adhesive.

Probably the best way to fix this is to just download the file and play it from a device like a civilized person.