I have a Galaxy S6 running Nougat and Samsung Music v18.104.22.168 (the latest version). The Smart volume feature doesn't seem to do anything. When I turn it on and off, I don't hear the volume change, and some of my songs sound much quieter than others regardless of if I have it on or off.
As far as I can remember, this feature has never worked since I got my phone in late 2015. It wasn't really an issue until recently, because all of my music was of a similar genre and volume level. Now I'm getting into some older, quieter stuff and this problem is quite annoying.
Any suggestions? I would really like to keep using Samsung Music, it's such a great app otherwise. If there's no way to get this working I will probably end up normalizing my entire collection using MP3Gain, but that would be quite a project and seems like it shouldn't be necessary.