Well, Since I didn't see a integrated way to mute or lower the sound in the Mini fighter's demo I found my own way. I right click on the task in my task bar then click "Indie Volume" . It's a great tool that I obtained. It allows for the user to increase, decrease, or mute the sound of a specific application. It comes with a few extra features that allow you to add effects to the sound, such as cave and arena sound effects.
I find this application very useful on more than the mini fighter's application. The Indie Volume program is made by Gerixsoft and you can buy or try this software at "Indievolume.com". If you want to know more or ask some questions come and stop by the Dark Eden forums located at DARKEDEN.TK -- DarkEden.ucoz.com. All are welcome to chat in our new community.