If it's simply the master volume that's down or muted, it's really simple because all you have to do is start alsamixer and arrow up; then escape and try something--espeak for instance. If that doesn't work, open alsamixer again and this time try pressing m to unmute and then escape .Test again. Admitedly though, if it is anything other than the master volume, it's really hard to do without speech. I realize I probably haven't told you anything you didn't already know.
