According to the Recording Industry Association of America, music piracy is the main reason that industry revenue has been cut in half since 1999, and the stars are fed up.
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"The whole music business has suffered because of piracy," John Legend told ET.
Last year, Taylor Swift was visibly uncomfortable when a British interviewer asked for an advance copy of her album, 1989. The pop star denied the request, saying, "It's not out yet. I don't even want to talk about it. I don't trust technology. I don't want to talk about leaks. It freaks me out. I'll have a meltdown on your show."
And it seems no one has been able to avoid the effects of piracy. Unfinished songs from Madonna's upcoming album, Rebel Heart, were stolen before she was ready for anyone to hear them.
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"I was very upset about having my record out before I was finished," Madonna said. "Nobody wants the work out before it's finished."
Billboard magazine editor-at-large Joe Levy says that pre-release piracy often happens while the music is still being produced.
"That music is on a computer; that music is on a phone; that music is vulnerable," Joe said.
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At the GRAMMYs on Sunday, Recording Academy president Neil Portnow addressed the piracy problem.
"For the artists, songwriters and producers we must promise them that new technology and distribution will pay them fairly," Neil said. "A song is just as much a property of the creator as somebody that built a house. If that's taken away from you, that's like ripping your heart out."
Nowadays illegal music is just a computer search away and the RIAA let ET into their top-secret war room, showing some of the tactics they use to take down pirates.
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As the culprits are uncovered, a cease-and-desist demand is immediately sent. There were approximately 20 million take-down notices sent in 2014 alone.
"Where it hurts people is down the line writers, producers, musicians are just going to make less money because they're getting paid from the sale of recorded music and fewer people are buying recorded music and the value of recorded music has gone down," Legend said. "Then it hurts them more than anyone else."