Just an additional note:  

Whichever preset you are wanting to adjust, 1 or 2 in the selected bank, you will be using the footswitch that activates that particular  preset.  For instance, if you are in bank 3 you will hold down the left footswitch to activate and adjust the output level as described above for preset 3:1.  To adjust the output level for 3:2, you will use the middle footswitch.  Just wanted to clarify