I just purchased a 7 plus a few days ago and I've been trying to add music to the iTunes library so I can sync it to the phone, but every time I add a file, folder, or I drag and drop stuff iTunes just freezes and it stops responding. I've uninstalled and installed at least 5 times. All my music is in mp3 format, I'm not sure what could be the problem. This is my first time ever using an iPhone and iTunes, so frustrating when on Android all you do is swap the microsd card. Does anyone have any suggestions? Thanks in advance.