Using iTunes' "Show Duplicate Items" feature, you can locate and manually remove duplicate songs on your iTunes music library. Once the library is cleaned, you need only sync iTunes with your iPod to remove duplicates from your device as well. This guide takes iTunes 12
to remove song duplicates.
- In iTunes, click "View > Show Duplicate Items" in Music module;
- Compare the listed song duplicates upon artist, album, date added, genre, play count, size, bit rate, and more to determine which item to keep and which item to remove;
- Hold the "Ctrl" key and click each duplicate you wish to delete.
- Connect your iPhone 6 to PC, click your iPhone from the device list, hit "Music" and select "Sync" to sync your library using your existing sync settings.
By doing this, you could delete duplicate songs on iPod from your iTunes. But it will eat a lot time of you. To save your time, let's come to the 2nd method - using 3rd-party iTunes cleaner program.