Bizzare squeaky-voice problem on Skype

I've been using Skype recently, mainly to talk to my girlfriend who has a PC laptop. Everything's been working fine until today when I tried to call her on it and her voice on the other end was all squeaky and high pitched. It sounded like the chipmunks, or pinky and perky, like a sped-up tape or something.

Apparently I sounded normal on her end. She hasn't changed any options on her computer. I did just update to the newest version of Skype so I wonder if that has something to do with it...?