You are most likely swinging the club from too far outside and over the top. I had the same problem. I suggest you spend some time at the range with an alignment stick or a cheap substitute like a yard stick or even an iron. Lay it on the ground on the opposite side of the ball from you and point it right at your target. When you swing your driver, use a slow back swing and on the down swing keep the swing parallel with that sick and stay on the inside of it. This will keep your swing nice and straight. Make sure you follow thru with your hips....and finish with what some people call the super hero pose...belt buckle pointed at the target, chest out, and upright!
Keep practicing and let us know how its going.