Problems syncing and playing local files

Using Studio version 2.3.0 on an M1 MacBook Air. A number of my local albums only display some of their tracks, and some of the tracks that do appear won’t play - I get a message saying “Unable to open audio file for playback.” This happens whether I add my iTunes music folder or sync with my iTunes music library. I can work around this by using the Legacy mode, and select/play tracks using the Apple Music app, but the problem shouldn’t happen in the first place. I’ve tried disconnecting from my account and re-connecting, but that didn’t help. I don’t have this problem with Tidal.