How to route external effects via spdif to audio interface (UR28M) in Cubase?

[mofat]

Please help me out. I tried today but no luck. I tried creating a bus with both the input and output via vst connection. In the INPUT tab I selected stereo spdif but I'm not sure what I select in the OUTPUT tab cuz it didn't give me the spdif selection.
Someone on the net suggested to create a bus in the External FX tab...tried that too. I changed the clocking to spdif and it didn't seem stable....like it flickers a lot. Anybody?

 

[mixsit]

I thought this might have been covered here recently, but didn't see it in a search.
https://homerecording.com/bbs/general-discussions/newbies/external-efx-cubase-307116/
Ran across this though..
Recording 101 - How to hook up a hardware effect in Cubase - YouTube
You will need the extra in's and out's on your interface.. at least a mono send, and a pair for returns. SPDIFs if that's what you have..