Connecting a UnitiQute to an HDX over Wireless

Have just bought a UnitiQute and attached it to the wireless network that includes an HDX. I can get internet radio ok but it does not find the HDX.

I have the HDX connected via UPnP to an Arcam using a Western Digital TV Live box and it works ok. The WD TV Live is connected to the Arcam via an HDMI connection. The UniQute cannot see the HDX at all and I am at a loss to understand why not. Must be something obvious?

For what it is worth, the HDX and Arcam are downstairs, but the signal where the Arcam is located is a lot weaker than where the UnitiQute is located, which is upstairs. The iPhone Nserve app can connect to the HDX from the same room as the UniQute.