I am building a footswitch board for a software looper , and need to be able to change the volume on each of four channels . I can do it in a roundabout way by controlling the cursor on the GUI with macros , but it would be simpler via midi. I have a midi continuous controller that I can use via cc#7 but it will not work because if I switch from one channel that is on volume 127 to one that is 108 the controller needs to start controlling at the appropriate level , not impose it's existing setting (the position of a variable resistor). So instead of the continuous controller what is needed is an instruction in midi that just says "volume down" if I press one button, and "volume up" if I press another. Any pointers to where I could go with this greatly appreciated.