Serato DJ Pro or your operating system may not recognize the unit as a controller.

Mac

Follow the instructions in the troubleshooting guide [here].

Windows

Refer to Case 3 in the guide [here].

You may solve the issue by doing the following:

- Disconnect any USB hubs and connect the unit directly to your PC/Mac.

- Disconnect any other USB devices.

- Quit all other applications.

- Connect to a different USB port.