I just recently upgraded from a Model 16 to a Model 24 and am having issues with the Main channel. I mainly use it for recording at home so I use headphones to monitor but the Main fader doesn’t seem to do anything to the sound coming through the phones. All other faders seem to work as intended and I can hear the mix but its as if the output is set to something other than the main channel even though i have the main switch on for every track. Anyone else had this issue?