Apple Music (formerly iTunes) will never play a full track, always skips after a few minutes

Almost every file I play via Apple Music (formerly iTunes) will not play the full track. After between three or four minutes it just moves onto the next track. I have a large music library (about 400gb) that I store on an external drive that is powered and connected directly to my iMac via USB C. I am running Monterey, latest version. Most of my files are 320 MP3s.

I have read every other post I could find on this subject on this forum or on Reddit and can't see a fix. It basically makes my Mac unusable as a music player and I have been storing my music in this software since about 2004. I can't use Homepod or other local streaming products for this reason.

I have tried moving my music folder to a fresh external drive, deleting and reimporting some of the files, clearing cache. I do not use Apple streaming, everything has been imported from CDs or bought from stores like Bandcamp. If I import any skipping files onto my phone from Music they play completely fine. I am not using soundcheck or the fader setting.

The only other unusual thing I have noticed is that sometimes Music takes a really long time to shut down, it seems to hang on "saving music library". I also sometimes get the issue where there are little exclamation marks next to all the files, presumably because the machine woke from sleep faster than the drive spun up. I can always fix this by closing Music and reopening it.

I have seen a few people suggest that my library file is corrup and that I should just completely reimport every file in my iTunes folder (it is still called this) but I would rather not lose the import date of my files as it's quite a good way to keep track of them all. I would be prepared to do this as a last resort though.

Thanks for any help this is driving me mad!