All pins are connected to the ground.
So basically there's a resistor between every pin and the ground. This way the pins won't measure noise when they are no connected. W
Ok, here's the thing: it's gonna be a modular synth interface. Analog inputs are for actual banana plug inputs of the 'synth'. Every time you plug a jack in the input, it should measure the voltage. When nothing's connected, the analog input should measure 0 volts, meaning that nothing's connected:) Once a connection is made, the arduino prints a serial message.
Here it's only pin 0 connected and measures 685 yet other pins read voltage (they totally shouldn't!). Why? Is it interference?
any time a single inputs gets voltage and is read, at least four or five other pins show voltage.
All the pins are connected to the ground through the resistor.