Weird Audio/Noise After Starting Taco (sound file included)

Hey all, new Taco owner here and i've started hearing a really bizarre sound after the truck starts. I've attached a link to the sound i'm hearing, you'll know it when you hear it. For the life of me I can't figure out what this might be. I don't have an alarm system (unless the dealer failed to mention and its not installed in the engine compartment) and haven't done any mod'ing to the truck myself. It does have a trailer brake controller but I do not have a trailer hooked up. Recently I took the Taco in for a new set of tires and they mentioned my battery was getting pretty close to done, so I was thinking maybe it was some kind of alarm associated with that? I'm newish to working on cars myself and I'm really out of ideas on this. Google seems to only return results relating to noises being made by the engine or something mechanical sounding. Not this.

Anyway, thanks for any ideas you all may have!
https://dl.dropboxusercontent.com/u/2098931/Truck.m4a