Several iTunes users have taken to the Apple Discussion forums to complain about iCloud Music Library — part of the iTunes 12.2 update — has destroyed their music libraries.
Discussions user Tuff Ghost explains that everything was fine with his 13,000 song iTunes library, until he installed iTunes 12.2 on his Mac and allowed it to enable iCloud Music Library.
“All of the (sic) sudden it starts overwriting my album art with completely wrong art (example: Weezer showed art for a Radiohead album) on both my iMac AND my iPhone, screwing up metadata by putting random songs in albums where they didn’t belong (there was a Cursive album where the first track was listed as a Foo Fighters song).”
When he clicked to listen to a song, it would play a completely different one, like the metadata for the files was completely incorrect.
If this is happening to you, another Discussions user may have found a solution.