about to ask a question but i saw this.
i think i got rid of them, haven't heard anything lately anyway. what happened was i was watching tv, "man vs. wild", where he took some awful urine/amonia smelling plant and stuck it in a hole to run out something he wanted to eat.
since it's a storage type space that i don't try to have as living space or whatever, and also since in summer it gets pretty hot, i took a bowl of amonia and put it up there. i was worried about it smelling up the house but that hasn't happened. i figuered the heat would help with the fumes spreading around.
haven't heard anything up there since.