iTunes downloading duplicates of podcasts and Apple Music tracks

Do you have any anti-virus software that could be snagging the iTunes files? Whenever you do anything in iTunes it writes out a new temporary file, deletes the original, then renames the temporary file to replace it. If you have the XML file enabled that gets rewritten too. When everything is working normally the temporary files flit in and out of existing as you make changes in the library, a track completes playing, and so on. With iTunes closed it should be safe to remove all temporary files in the iTunes folder. If possible exclude the whole iTunes folder from any real time AV monitoring.

You can use File > Add to Library and select the iTunes Media folder to add in any content this isn't currently listed in your library.

See Find and remove duplicate items in your iTunes library - Apple Support for Apple's advice on removing duplicates. Reducing the view to Same Album duplicates and only deleting those added most recently (you can sort on the Date Added column) should allow you to clean up without losing information. Or see https://dougscripts.com/apps/dupinlite2app.php for a possible deduping app which might be better than doing it manually. Ideally you would start with a complete backup in case you get over eager at any point and need to pull something back.

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Make sure that your profile has full read and write permissions to the iTunes folder and all subfolders. Use Get Info on the iTunesfolder in Finder. Click the lock at the bottom right to make changes. Make sure that Locked isn't ticked and that your own account has Read & Write access, then use the gear icon to Apply to enclosed items and confirm.

If your media folder is not stored inside your main iTunes library folder then make the same changes to the media folder.

You also make a new library in another location and see if that behaves normally. See Open a different iTunes Library file or create a new one - Apple Support if needed.

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Close iTunes. Delete the content of the downloads folder inside your iTunes Media folder. Start iTunes.

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Ah, got it now. I'm guessing you're looking at repeated issues of Empty/corrupt iTunes library after upgrade/crash that are masked by the fact that you have Apple Music, and perhaps options for automatic downloads selected. You could use File > Add to Library to import the entire iTunes Media folder, then deduplicate the library to slim it down again.

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