Ed/Knut,
I don't remember if you are using the mission engineering pedal or not, but if so I just swapped out the on/off switch in mine and it makes a HUGE difference in toggling the stomp A slot.
I used to struggle in switching from Wah to volume as the switch is momentary and didn't have the normal hard click you get in a Wah pedal. Changed it out to a different switch with a positive click, works 100% of the time now.
Sean