Follow the steps below if your system does not have audio output:

1. Ensure that the computer is on and not in standby mode
2. Make sure that the HDL200 is connected to the power supply and plugged into a power outlet
3. Verify that the USB cable is connected from the USB port on the HDL200 to a USB 2.0 port on the computer
4. Confirm that Echo Cancelling Speakerphone HDL200 is set as the default audio device for your operating system and for your software (UC&C software)
5. Confirm that the volume output on your operating system is set to an audible level
6. Confirm that the volume output of your software (UC&C software) is set to an audible level