FiiO K9 Pro ESS Desktop USB DAC and Headphone Amplifier with Bluetooth - Manual (Page 4)

C. Connect the K9 Pro to the output device and select the
corresponding output mode.
D. Make adjustments to the gain and volume to suit your preference.
To Learn More
1. The K9 Pro can be controlled by FiiO Control App. For more introduction, please
visit https://www.fiio.com/
2. The K9 Pro operates driver-free on Mac OS. For Windows users, please visit our