Hi I have purchased a code 100 h with the idea of using it with my unpowered Kemper , so when i run the kemper into the return on the code it seems to bypass ALL the front controls including master volume ,  on most amps it would bypass the pre-amp dsp section but be before the master volume so how do i control volume from the amp , i havent had this problem using the return of any orher amp , Also it seems to be quiet in comparison to my katana 100 watt head which is also solid state ? TIA