My phone updated yesterday, took an hour to complete, and issues with Music started immediately. I've no degradation in sound quality, but (1) it has crashed a few times, (2) scrolling through playlists is jerky and slow, (3) album thumbnails don't always appear, (4) when one song finishes playing the next starts ok but the display still shows the previous song playing and the currently playing song next in queue, (5) when I start playing from a different playlist it doesn't always start playing, it displays Loading then fails and displays Not Playing, or occasionally reverting to the last song playing from the previous playlist, (6) (not an issue, just an annoyance) if a favourite song appears at the bottom of the queue and I want to move it to the top, when I click and hold the song the options have moved round and Move to Top isn't in the usual place!
There are other issues not connected to Music, eg my Notes are now all saved on iCloud, it seems. Lucky I don't have any personal information in them. Same with my photos. A few (not all) apps are very slow to load. A small number of websites need me to remember my passwords because my phone has forgotten them. Like I can remember 16 character randomly generated passwords! And last, but by no means least, the battery appears to be draining faster than usual, same as happened after several previous iOS upgrades, some of which took several further fixes to correct fully.