Random warcraft III mortar team voice lines playing

Hi everyone. I got a weird problem: random warcraft III mortar team voice lines keep popping up. Even when I'm not doing anything. Is this a part of an ongoing event? I tried to search the forums but I didn't find anything. I've just started playing, playing as a gnome rogue on a lorderon server (using the wraith of the lich king client, not the old version). It's frequent enough to where it's too annoying to play. I don't have any addons.

Edit: I guess I will just reroll to play as a horde. Still curious what the fix is if it does exist.