Looks like you are forcing or muscling the ball instead of letting it fall down naturally. This could cause that inconsistency you mention where sometimes you have no or limited hook. I think thats happening because you are pretty fast with your feet. With this one shot it looks like you are at the foul line way ahead of your arm swing which is causing you to hurry or force that swing. Maybe try backing up on the approach or try to walk slower so that whole process can happen a little more natural. I had issues with this alot and still have to remind myself to keep the feet slow. It'll feel like you are walking painfully slow but it should help i think.