The DAC-2 has the ability to program the volume to a Variable or Fixed setting. The unit will arrive in the Variable mode which is desirable when using the unit as a pre-amp. The variable setting allows volume to be controlled in the DAC from 0-70 with the floor pre-set set at 23 (see Max/min volume Feature FAQ). If you are using a pre-amp the Fixed Volume feature will most likely be the desired setting. In the Fixed Volume mode the DAC-2 will output max volume or whatever value you have set for max allowing all tuning to be done through the pre-amp. Fine tuning the Max volume of your DAC in fixed mode will allow your pre-amp to operate in a volume range that is desirable for you. The settings can be customized for each input independently. The section entitled Fixed Volume mode will explain this feature and the section titled Setup mode will explain how to program the unit to your specific needs.