I agree with mazing that it might help to talk things out with your parents. One way that may help your situation is to ask questions rather than make statements (other than direct statements of how you feel), those can be taken as accusatory and feel offensive. You may find more luck getting each parent aside one on one. Ask questions such as:
Ive noticed lately you have been fighting, what has happened??
Is there anything I can do to help?
Don’t be surprised if they don’t confide in you great detail about what is really going on. Parents sometimes try to shield their children from the real hurt that is associated with the fight. Also, they may keep fighting, but do it more out of ear shot from you once they see how you are being affected. You are a member of your family and your feelings matter. Just be careful how and when you confront them.