Yes you can, your voice is not 'fixed', that is simply not true. You can learn to speak through different variations of using your vocal cords. For example:
Yawn. Doesn't matter if its fake or not, yawn. Then speak as your yawning, this is lowering your larynx(ball in your throat) and loosens your vocal cords.
Also, just try to speak through your chest, breath in deep, and talk out slowly, with the air coming DIRECTLY from your chest. Hope that helped.