A broad singlet at 2.27 ppm?

I took the $\mathrm{^{1}H}$-NMR (CDCl3 solvent) of my product, 2,2-dimethoxy acetic acid. Below is what I see:



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> $\delta \: \pu{4.862 ppm}$ (1H), $\delta \: \pu{3.521 ppm}$ (6.78H), **$\delta \: \pu{2.271 ppm}$ (5.39H)**
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Peaks at $\delta \: \pu{4.862 ppm}$ and $\delta \: \pu{3.521 ppm}$ indicate my product I believe, but I cannot rationalise a peak at $\delta \: \pu{2.271 ppm}$. 


I did dry my organic phase over $\ce{Na2SO4}$ so this cannot be water. I have never really seen a broad singlet in 2-3 ppm region. Does anyone have any idea what this would be? Would appreciate any thoughts&ideas.


