iTunes has become hugely unreliable...

I have 10+ years of purchased music stored on our server. Now, in the last two weeks, iTunes has mangled my library on multiple devices, on a variety of OS's and iOS's.

It is my good fortune, and foresight of Apple's planned obsolescence, that I have regular backups of my PAID music library.

I am looking for an alternative to play my PAID FOR MUSIC, on a variety of operating systems on the Mac for playing my music. iTunes is clearly trying to sabotage my collection and I don't appreciate it.

Yes, I am a subscriber to Apple Music. But that should not jeopardize my ability to OWN the music I have meticulously purchased over the years.

Thoughts, comments, criticisms, suggestions for alternatives?