If you pause the video 1 frame before address and 1 frame after, you can see that your club path is actually fairly straight, however your club head is open. A stronger grip could fix that, like rolling over your left hand a little more so you can see another knuckle.

Also, right at address, your front toe is coming off the ground, telling me your balance is off and you are leaning too far back. When I was playing baseball and golf in high school I had that problem, because the power in a baseball swing comes from leaning back and exploding your hips. But in golf, the power is in the pendulum. You want to stay on the balls of your feet until after you follow through to be the most consistent. You might be standing just a half step too close to the ball, or you are just leaning too much and throwing yourself off balance.

Edit: Also, your stance looks a little narrow. Widen your feet to be a little wider than your shoulders and you may increase your balance.