External FX problem

Hi,

My external effects reverb unit (Lexicon PCM92) stopped sending audio thru Cubase suddenly today. was working fine previously. Deleted and re-added it in the Exernal FX tab and it now shows an ‘x’ next to it. The reverb unit receives a signal but it does not seem to be coming back into Cubase. The delay also does work anymore. Attached are screen shots.

Here’s the info on my setup:

Cubase 10.5.5
iMac 3.2 Intel Core i5, OS 10.14.6 (Mojave)
Audio interface: Apollo x8

Can anyone help please?
much appreciated!!