After last update (576) Groove stopped playing. I mean no sounds were heard even though the song was running. My songs were playing Ok in other applications.
I tried reboot - did not help.
The solution: Uninstalled Groove with CCleaner (it does not appear on the Programs and Feature list) and reinstalled it from the Store.
Does it seem regular to you?
I do wonder which Last update for which Edition.
but in general.
1. If the Insider Edition - known buggy as hell and many updates kill some old it worked.
2. if 14393 edition - some minor updates were buggy (known by MS)
3. if 10586 edition - actually the most stable of all. fewer bugs allowed. until they force you into 14393.
FIX in general open updates and uninstall the last one... reboot.