Endless zombie spawning with base defence that sets them on fire

[lolsteamroller]

Using consecrated soil for base defences, and already tuned spawning variables to be way lower, on some nights (playing with staying up enforced), it starts endless spawn waves, especially if they step on the soil (which sets them ablaze), haven't checked other damage sources).

It spirals out of control really fast. Figuring on what the problem is, it's either - the zombies on fire are not considered zombies (unlikely, since they can't all be on fire), or the sound they make spirals out of control - they do scream when on fire).

Would love to have to fix this, because in 20 seconds it can go up to hundreds of zombies, and most of them doesn't respect light level to spawn in, resulting in big slowdown for server, until it's reset through difficulty peaceful and back to hard.