Oh man, that's miserable!! The only time I've seen that happen was when there was something wrong with a chick -- developmentally something was just not right, and the chick wasn't flourishing, and the other chicks seemed to know it. I had that happen a couple of times when my incubator was running too low and some of the chicks didn't develop normally. That shouldn't have been an issue with a Brinsea, thought!
Chicks, individual pics, top to bottom (I'm pretty sure!):
basque
rhodebar male
SFH
rhodebar female
basque
Group photo, though,
looks like (and I emphasize the "looks"): 2 rhodie females, one rhodie male, one basque, two SFH, the one in the dish could be either a light rhodie male or a dark basque (if it's got a dot on its head, it's a rhodie male), and the greyish-looking one top right could be either a SFH or a blue isbar. If the legs have traces of black or green "surface" coloring, it's an isbar

And you have a very cute hatchling there, yourself! I miss mine

He's all grown up now!