Guys, I pulled out all of my basses this evening and I was playing them all acoustically and I noticed a strange rattle coming from my T-40. It only happens when I play an open A-it sounds like the string is vibrating on something. When I push down slightly on the string BEHIND the nut, the buzzing stops. Now before you all say "Raise the action" the action is already somewhat high because that's what I prefer. I was also thinking maybe there's a high fret but when I look closely at the frets, the frets seem to be more worn under the A than anywhere else. I'd hate to start modding this thing but I'm wondering if I should get another string tree since that little bit of extra downward tension really seems to make a difference. Or maybe its an issue with the nut? I'm open to suggestions!