Q: incomplete tracks of previously purchased music

Hi there ddorwichflute,

It sounds like you have a couple of tracks that don't play completely. Rather than deleting the albums altogether, I would instead delete the individual songs themselves one by one, and test them out again. 

Delete songs, playlists, or other items

Delete an item from your library

1. Click the item to select it, and press the Delete key.

2. Click Delete [item].

3. Do one of the following:

    
    
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     Remove the item only from your iTunes library: Click Keep File.

      
    
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     Delete the item from your computer: Click Move to Trash. The item is removed the next time you empty the Trash.

      

Deleting an item from a playlist doesn’t remove it from your iTunes library or your computer.

If the issue persists then I would next create a new test iTunes library and try downloading the tracks there:

Open a different iTunes Library file or create a new one

Shouldn't have to authorize the computer again, but if you do:

Authorize your computer in iTunes

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