A new sound pattern that your brain doesn’t recognize will always stir interest in your mind and wake you up. Even though you might get carried away by a repetitive pattern in music and fall asleep to it, a sudden change in that pattern will immediately wake you up. That’s the natural defense mechanism of your body. Without recognizing odd sounds, we wouldn’t be able to protect ourselves from potential problems around us. Moreover, if you like the new music you hear, it’s a high chance that this is the reason why you find it more difficult to fall asleep on it, just as in the case of an interesting movie or book that catches your attention. I personally recommend playing white noise instead of music before sleep. In my case, Sleep Automatic did the job, but it’s ultimately your choice. Hope I helped!