Don't know about the stuck up or down, but, the dropping 3 or 4 inches is a "safety" feature. Some guys who put on in channel vent visors have the problem. It's in case your kid sticks his arm in or something. You can reset it by taking your door panel off and I think there is a button to reset the stop point. I know there is at least one thread on that. I will see if I can find it and maybe link it here. Don't know if I can link it with my phone though.