ipod services centres

how do i downgrade my ipod version?
i had to restore my ipod so i brought it to the apple service center so i won’t lose my itunes data. but the store’s itunes version is 7.7 and mine’s 7.6 so it can’t be synchronized. does anyone know how to fix it cause i’m afraid if i download itunes 7.7 i’d lose all my data and i have like 800 songs.
You wont lose your data ,download 7.7.If you lost your data every time you upgraded itunes, no one would upgrade.
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