If you had to get permission, these millions of sound-alike tracks wouldn't exist. There's a compulsory license for cover songs, but the question becomes: is it

If you had to get permission, these millions of sound-alike tracks wouldn't exist. There's a compulsory license for cover songs, but the question becomes: is it still a cover if a machine does it? Or does it infringe the recordings' copyright since it's merely a "processed" version of the original recording? And how would you tell the difference between a human-cover and a machine-cover? Interesting times ahead...