Hatching late is generally due to either low heat in the incubator or the eggs themselves. Do some investigation into your thermometers to make sure they are accurate. Even a half degree off will delay a hatch. And if you can not find anything wrong on your end, then find a new source for your eggs. It has to be one of these issues.Hmmmm...I have none of these problems so I am presuming that I do not have a high humidity issue. Yet still, this time I'll try to hatch at 60% instead of 75%. Will keep you posted!