I'm not sure where to post this so I'll start here. I've noticed a bump appearing in my floor. The foundation of my house is made from block, and down the center of the basement there is also similar block as what goes around the outside edge. One the first and second floor, directly over this block wall that goes through the center of the basement. I'm noticing a bump. It's probably 1/2" or a 1/4" raised in a couple places. Does anyone know what could be causing this?