Music is playing at reduced speed and skipping with Desktop app

My songs in Apple Music have started to play at a reduced speed, and with skipping during playback.

This not on iOS, but on Desktop, and not streaming but just listening to tunes downloaded to my Mac, making listening to any of my music impossible.

This occurs whether or not I'm signed in to my iTunes/Music account, and on all songs – even those imported 20 years ago.

I can't be sure, but I don't think this was an issue until the last OS upgrade (Sequoia 15.3.2); I'm running an M1 iMac.

Anyone else having this issue?