Windows 7: Changing default sound device with a macro?

I have received a new "Microsoft Comfort Curve Keyboard 2000" that will allow me to change the extra buttons it cause with i.e. the back and forward page buttons, but i've never cared or used them when web browsing, and what i'd like to change it to is to switch between my different playback devices, (one for each button of course, like the back button sets it to speakers, and the forward button sets it to headphones) but i'd need a "text" macro if that makes any sense it will allow me to make my own macro, because i know some keyboards or well programs that come with your keyboard will track your mouse and record it's own macro for you. Any help will be extremely appreciated!