Cubase 8.5 External FX Hardware Routing

I just cannot get this to work and wonder if someone can point out what I am doing wrong.

Im using a Mac OS X Yosemite with a Lynx Aurora 8 Converter and Cubase 8.5.
The Lynx is set to 16 channel mode and has USB 1-8 as the 8 Analog IO and USB 9-16 with the 8 Digital I/O channels so basically Cubase sees 16 channels of USB I/O in Device set up.

I have only two Tracks set up in Cubase 8.5 Track 1 Stereo with an audio recording on and a FX channel track with my hardware external FX on. This external effect is connected via its AES IO through the Lynx Aurora on USB Channels 15 and 16.
The External FX device set up has Send and Receive allocated in VST Connections External FX as per pic below

The VST Connections output are set to USB Play 1 and 2 Stereo out

I play the track and can hear the audio OK

I then add the External FX as a Send on the Audio track and turn it on send and return levels all at 0db on the external FX and on the track but I get nothing, no movement on the FX Effect meters no audio passing to it. If I add an internal effect to the track in the same way no problem meters show audio passing and internal effect added.

What am I doing wrong on external fx routing? All help suggestion appreciated.



As a first test, try to use your External FX as Insert plug-in of the Audio track, please. Does it work?