Every time i play the D string on my acoustic, it buzzes :S

I was hoping someone can tell me why its happening, plus some solutions,

Thanks in advance
this happened to me and there was a mouse in my guitar. no joke.
My Guitars:
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All the kids in the coffee houses
try to act like they know what loud is
all they know is an electric beat
if you're rockin to this, you'll be rockin with me!
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what does luthier fixed mean?

a luthier iz a guitar maker and fixxer.

We'll choke on our vomit and that will be the end

We were fated to pretend
a lithier makes and fixes guitars. he said, have a luthier FIX it
Peavey XXX combo *upgraded screen resistors, Tung-Sol's, and 6L6's*
Schecter Syn Std. * modded, scalloped, and worn*
Schecter C-1 Elite *still sexy*
Ibanez AEL 12-string

"He who sticks his dick in peanut butter is fucking nuts"
My old acoustic used to do that on the high e string. I figured out it was the bridge, so the next time I changed strings I just stuck a small piece of cardboard between the bridge and the string just to raise it a little. Fixed it perfectly.
But if that doesnt work, or if its actually a decent acoustic (mine cost me a whopping $150), then go see a luthier and get him to fix it.
"Hey its that Barbeques over sound again!"