The launch of Apple Music and iTunes 12.2 has had it’s fair share of issues, which can be expected when a giant new service is integrated into older ones.
One of the most common seems to be with iTunes libraries becoming disordered and incorrectly linking to albums after enabling iCloud Music Library.
For whatever reason this is affecting the metadata of some libraries’ music and so until Apple fixes the issue here’s a simple solution:
Navigate to your iTunes folder
Choose a former .itl file from Previous iTunes Libraries (the most recent one available before the problems is recommended) and drag it into your iTunes folder
Rename the broken .itl to iTunes Library (Corrupt).itl
Rename the .itl file you just moved to iTunes Library.itl
This should fix any problems however make sure not to accept the request for iCloud Music Library again until Apple has resolved the issue.
Thanks to Zackadelic on the Apple Forums for the solution.