R31, C9 form a low-pass filter.

Tools Needed

• Soldering iron
• Cutter

Parts Needed

• 1 x 4.7kΩ resistor
  
• 1 x 0.1μF capacitor
  

Instructions

1. Solder the 4.7kΩ resistor into R31.
   
2. Solder the 0.1μF capacitor into C9.
   INSERT PICTURE OF CAPACITOR BEING INSERTED INTO PLACE.