Doc, that frequency and midrange control section is a parametric EQ. The frequency is selectable and then one can either cut or boost the selected frequency range. With the Midrange control at ‘noon’...zero, you can sweep the freq range all you want and nothing happens. Re: “the volume on 2”......dime the master volume and then turn the channel volume to 2. What does that do? There is something wrong with that Multifilter section if it is drastically affecting volume.