Just press a button and a song comes out -- can't be copyrighted. I wonder: what would it take for a machine-generated work to be considered a work derived fro

Just press a button and a song comes out -- can't be copyrighted. I wonder: what would it take for a machine-generated work to be considered a work derived from a human-generated work? While the machine-generated work still wouldn't be copyrightable[0], would that prevent others from using the machine-generated work without an appropriate license? (IANAL.) [0] «To be copyrightable, a derivative work must incorporate some or all of a preexisting “work” and add new original copyrightable authorship to that work.» https://www.copyright.gov/circs/circ14.pdf https://www.copyright.gov/circs/circ14.pdf [PDF]