I had a rat, or two, in my pantry last year. It was horrible! Had to throw out so much stuff because they'd chewed through packaging, or even just pooped on it.. My pantry got a good clean and was very organised afterwards though! I'd try peppermint oil if you can get your hands on some.. Chemist? Health food store? Maybe even the soap place in Wagga? As for the noise thing, I've never heard one but would it just be like white noise for a baby? Plenty of things we find annoying can be quite soothing for a baby.