Only previous problems with my bass has been adjustment of string volumes...and have found useful articles. Have now found a major problem. Half of my bass models aren`t available..Can anyone suggest how my selector switch when pushed now cannot access all the "red bank" models? Is this a mechanical or electronic problem?. I`m careful with the selector switch and it still appears to click down...but stays on "green models" only. Advice gratefully accepted. Thanks, Roy