The Link Box supplied with XR-1 Developer Edition, VR-2 Pro, VR-2, or VR-1 cannot be used with XR-3 and VR-3.
XR-3 and VR-3 are connected using one or two headset adapters provided in the sales box. Note that you should connect the headset to the headset adapter(s) and not directly to your computer. See detailed instructions on how to set up your headset.