How do I select the USB Audio input on the EXA100? 6 months ago Updated You can select the USB Audio input by selecting the 'USB' button either via the EXA100 front panel or remote control. Related articles How do I use the Control Bus connection on the EXA100? The EXA100 Speaker A/B light is flashing blue, what does this mean? What DAC does the EXA100 use? What is the EXA100 Power Amp Mode? What is the best way to connect the EXN100 to the EXA100?