Album/cover art missing on iOS devices
I copied an album that I bought outside iTunes (amazon) on my iPhone/iPad manually using the Music app on BigSur and on both devices the cover is not displayed, while the Music app has no issue.
I deleted the cover manually and added another one (JPEG, 600x600, 72dpi) and it still is only visible in the Music app - not enough memory on the device is definitely no issue (iPhone 180GB free space, iPad 80GB).
Interestingly there are already several Albums on my iPhone for a long time that I bought in different stores (Amazon, Defected, Beatport) that are showing the covers. As these were all copied using iTunes on <=High Sierra, I'm not sure if this is an issue with the Music app - anyone an idea how to get this solved?
I restarted the iPhone/iPad, forced quit of Music app on both devices
iPhone XR