[arch-general] speakers don't turn off when headphones inserted

Hello, I just obtained a Fujitsu P7120 notebook (a very nice model, by the way). Overall, I am getting this working with Arch just fine (although I would definitely appreciate pointers from anyone else who has installed Arch, especially as I have been using a desktop until now and haven't had the need to configure notebook-type features). One problem I am having that I don't know how to fix is that when I plug in headphones, the speakers don't turn off. Alsamixer shows that the headphones and speakers have separate controls, something I have never seen in a notebook before. While cool, I would really love to have this automatically toggle as expected. Does anyone have a suggestion? Thanks, Scott