Wander spawns not attracted by NPC gunfire

I just turned NPC’s back on for the first time in a while. Within a few days they were shooting animals, and still getting slaughtered, all around me. If I fire even once, it seems, the wander spawns will show up but NPC’s can shoot all day long without wander spawns.
I don’t necessarily want the wander spawns to rush to the site of every one of my gunshots, but if some fool is letting it rip over and over then he deserves what he gets.

Linux Curses
0.A gdfe0184