Mine does the same depending on what kind of protein mix I use. Want to hear something insane? My Magic Bullet knockoff DOESN'T smell funky...how weird is that? I use it in the morning and just rinse it quick before heading out, and it never smells, but my shaker does. The GNC shaker I have at home though doesn't smell weird. I seriously wonder if it is the kind of plastic they use on the cheaper shaker bottles, if it's slightly porous or something?
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