So fitted a nextbase dash cam today and used the hardwire kit as in this post. And even when the keys are out the camera still stays on. I used the cigarette lighter slot of which I used the piggy back cable etc the hardwire kit that I have has a small square black box. Could it be that there's some power still in that which is why the camera is still on? Even when manually turning off camera the little blue light is still on indicating it's still receiving power. I'm gonna give it half n hour to see if it eventually turns off itself.