The widget on my s7 grays out after a couple minutes. I do not have any battery saving options enabled. I have also gone and turned off "save power" on after 3 days on Spotify. Nothing seems to work. After a couple minutes it looks like the screenshot
I tried to figure out what the **bleep** is the widget's problem and I arrived at the conclusion that it's a separate app. Spotify continues playing music, but widget grays out. Also on restart you have to open Spotify app, clicking on the widget doesn't work.
If only Apple Music would get its shiz together...
I went through those fixes so many times I lost count, including clean install of Android (and Spotify), uninstalling, reinstalling, cleaning caches, redownloading all my music five times, etc. Nothing can change the fact that it's just a terrible piece of software and it's been this way for as long as I can remember.