Hello, i didn't notice anythng like that, could you post your build to see what may be wrong?
My first idea was that you didn't turn on aspect of assault, but you did. So, which level are you and in which zone are you playing? For example, in KoE they rised the mobs' lvls from 70 to 73, so, those should be hardder than before, also, the new astral allods are hardder too.
To activate Pyrolisys you must crit, check your current crit chance.