If I do 4sh5sh6sh7sh really fast, some of the hatcheries just won't produce anything. I can reproduce this with a single hatchery as well - if I do 4sh fast, sometimes it will work, sometimes it won't. There seems to be a delay after larva selection until a key press is recognized for some reason.
Is there a workaround for this? It's driving me mad to the point of making me not want to play zerg anymore. I tried using a brown switch vs blue switch mechanical keyboard. I'm gonna try to get a cheap membrane keyboard to see if that changes anything.
edit: I've seen top zerg players with keyboard input view, and they seem to be pressing buttons super fast and not dropping any inputs after larva selection, so I don't understand what's going on..