A closed-form for $\sum_{n=1}^{+\infty}(1-\operatorname{sinc}(n^{-1}))$

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I'm trying to find a closed form of $$\sum_{n=1}^{+\infty}(1-\operatorname{sinc}(n^{-1})),$$but I have no experience in constructing a closed form before. Could anyone give me some help? The convergence is assured due to $1-\operatorname{sinc}(n^{-1})=O(n^{-2}), n\rightarrow+\infty$.