Puzzled on mono cable

[Kevinmac59]

I only use a mono cable on gigs. I normally keep the red button in but honestly I am not sure what it does when I use a mono cable. Any experience out there with this? Red plug in or out with a mono cable?

[Patzag]

Red button allows Piezo signal to be used using the mono cable. If the button is out, you will get no sound from your Piezo using a mono cable and you would need to use a stereo cable.