if it is just G than the key under your left ring finger is more than likely not closing. If it is G, and others, such as but not limited to F,E,D...then it could be that the key, just past the left pinky, is not closing.
If you haven't gotten that fixed, considering it has been three-ish months, email me for more information. Charmed1p5@yahoo.com.
Harumi, October 2008