Amazon is introducing a music streaming service on Thursday. The service will compete with streaming services that are already popular, like Spotify, Pandora and Beats Music. The streaming service will be an add-on to the Amazon prime subscription. However, the Seattle based retailer is having trouble getting some of the music it wants. While Sony Music Entertainment and Warner Music Group signed on with Amazon, the world's biggest record label, Universal Music Group, did not. Universal is the home of a dozen billboard leading artists, including Lady Gaga. Universal is not happy with what Amazon has offered. Unlike other music services, who pay the record label based on how many times a track is played, Amazon wants to pay a lump-sum upfront for each song. Universal is not the first media company seeking a better deal with Amazon. Movie studio Warner Bros and book publisher Hachette Book Group are also holding out for better terms. Because the hits from Universal are missing, other music services are not worried for now. And unlike Spotify and Beats Music, Amazon's streaming will not feature the latest releases.