"Never point out your flaws. Let others figure them out on their own."
Admit them if accused. But if you're being complimented, many of us will fall back on an anxious habit of self-depreciation. Unfortunately, that doesn't convey humility as we wish, and it may even put our kind complimenter in an awkward situation.
Accept the compliment with grace and appreciation. And if the flaw doesn't come up, then it probably doesn't matter!