> Why? Because two resistors in parallel (i.e when RD is shorted to RA) lowers the resistance and pulls the voltage down to a range that identifies the device

> Why? Because two resistors in parallel (i.e when RD is shorted to RA) lowers the resistance and pulls the voltage down to a range that identifies the device as an audio device to the charger :edit: A diagram to clear it up https://imgur.com/97OKDf5 https://imgur.com/97OKDf5 Top is as the RPI is effectively configured, Bottom is how it should be.