Bernie,
Hit the button "mixer" and then the part you are playing will be flashing under the screen. There are 16 parts and if you push the buttons, under the screen from left to right you are selecting the upper one, upper two, left, etc. You can now, once you've selected mixer functins use the curser up and down to select things like volume, pan, effects levels, octaves, etc. All of this is in the owners manual but you have to search to find them. Look in the section where "mixer" functions are explained.
George kaye
Kaye's Music Scene
Reseda, Calilfornia