I've had this problem at least since iOS 7. Most of my music is purchased from iTunes. Sometimes the release year in the metadata is inaccurate, so I change it in iTunes. When I sync to my iOS devices, it retains the incorrect year on that device. I've tried removing the music and re-syncing it. The issue has even persisted after upgrading to new devices and setting them up as new. All software is up to date. Has anyone experienced this, and if so, do you have any solutions?