The Doctor took care of several other Torx controlled people while Nora was looking for the PA system. The Doctor started wondering if there was a head Torx and what would happen after she took that Torx out. Where they a hive mind? Probably not, they all seemed surprised as she took them out. Then a passing thought, she was killing off all these aliens. Some of them deserved a chance too, but if they lived they'd kill all the humans. When Nora called her over she was making sure that the just fallen people had a heartbeat still. She stood quickly and headed over to where Nora was standing in a doorway. 

"Perfect." The Doctor grinned seeing the PA system. She walked over to it quickly. The Doctor flicked several switches hoping the same thing Nora did. When nothing happened she sighed. "Watch the door." She handed the "tracking" machine over to Nora. "That's the button you'll want to press if anyone comes." She then knelt under the desk and started messing with the wiring. The strange noise Nora had heard in the car repeated as The Doctor dug around under the desk.