I have the same problem at the end of my hatches over and over.the chicks pip and one or two makes it out and then the rest die.I have a hovabator.I pull the plug at hatch time. I try to keep the humid in the fifties the first18 days.sometimes it gets a little higher.on day 18 it goes into the 70's.if I don't keep it high it seem the chicks are stuck.but why do they pip and then die.I don't think they are drowning because the beak is out.