Not sure I’ve got a fix on exactly what’s happening, but since the last patch I’ve noticed that if I place a frost trap, the frost AoE often occurs somewhere else than where the trap was set. In a couple of cases, I was running away from a spot where I placed the trap (defensively), and the trap AoE appeared nearby me after I’d run a good 5+ seconds from the spot where the trap was placed.
I haven’t witnessed this when dropping a trap directly onto targets where it gets triggered instantly, though.