I just bought a used Sovereign XS-2A Pro and I should receive it in a few days and I have a question about it. I know that it doesn't have a ground balance knob on it. So how does one go about and adjust it to the ground. Do I set the threshold and the sensitivity until it doesn't false anymore and then it will be ground balanced. My other machines are have a preset ground balance. So I have a few questions. Any help will be appreciated. Thanks.