Above is a picture of the TMC2100 stepper drivers used in the Series 1 and Series 1 Pro. These are different than A4988s and DRV8825s, both used in older versions of the Series 1.
It is important to have your potentiometers set to the correct voltage. Under voltage can cause weakness in the ability of the motor to pull. If the voltage is to high, the motor and the driver gradually over heat which will cause an increase of skipping over the course of a print.
You'll need access to a multimeter in order to check the voltages on the stepper drivers. The stepper drivers are installed on the Rumba motion controller, which is in the E-tray on the right side by the power supply. As shown in the E-tray guide
The stepper drivers from front to rear are X, Y0, Z, E0 and Y1. Whenever you're tuning the pots on the stepper drivers, always use the white ceramic tipped screwdriver from your Type A Machines toolkit. Using a metal conductive screwdriver can short the entire Rumba.
To check the voltage on a stepper driver, set the multimeter to 2V. The red probe goes on the stepper driver within the lowest gold hole of the three on the face (circled in red). Place the black probe on any GND (circled in black) point, like the (-) coming from the power supply. Since these are metal, be careful of placement as not to short any components. The Trinamic TMC2100s in your machine have inverted pots (circled in yellow) on the bottom of the board, with a round hole to access and turn using the ceramic tipped driver.
For E0 driver, you'll need to adjust the pot as close to 1.0 as possible, with erring on the low side preferred. We use a range of 0.95-1.015 as acceptable for E0. If your E0 stepper driver is below this range, the stepper motor will skip steps. Clicking is a sign of over voltage in they stepper driver. It's hotter than normal and often results in missed steps.
The desired setting for X, Y and Z is 0.75V give or take ~0.03V.