Guitar Problems? (E-string)?

Well, my grandma let me borrow her acoustic guitar a couple weeks ago. It sounded awesome, until one day I picked it up and noticed that if I played the top E on the first, second or third fret it buzzed really bad.Other from that, it sounded great. I spent hours removing the strings, trying to see what was wrong, but it's nothing wrong with the bridge. Under the bridge there was a tiny little sliver of wood to raise the top E so it WOULDN'T buzz. When we tried to add any more wood or things to any other part of the bridge it would be catastrophic, so much that in the end it actually buzzed the least and sounded the best before we tried to fix it, when it was only the three frets on E it buzzed. Any suggestions?