Sync Preview - Always wants to delete random songs

[preciouschaos]

I haven't been able to sync lately because every time I try, it attempts to delete songs because it says they're no longer in my library, but that isn't true. I can't find any screwy tags or settings to cause it. These songs are in the list to copy either like sometimes happens when a tag changes. I don't know what to do. It's random as far as the songs go, but it's very consistent that there's always an extra song I'm not trying to delete when I sync and I can't stop it...

[phred]

Do a sync preview, make note of the songs to be deleted and then scroll further down the preview list to see if those songs are to be copied (synced) again. Typically the preview would say 'update' but I've had a few occasions where MB deletes and then copies upon a sync.