insurance and lien holder standoff?

As a lien holder we have been experiencing extremely low payoff amounts from insurance companies. The issue has been mainly with insurance companies using ccc one third party evaluations. Our customers are being left with large balances due to insurance companies not paying the actual cash value of the vehicle. They are giving a low base value of the vehicle and not willing to negotiate. They are wanting extra options added or extra info on things that are not in dispute in order to give a larger payoff.. Is there anything that can be done about this or is arbitration the only recourse that can be taken?