Soundtoys Echoboy keeps mulfunctioning when opening projects

Hi, since buying cubase 9.5.1 I keep getting this really annoying issue. All my Soundtoys echoboy instances don’t out put sound, like they’re disabled but they not, they open as normal - yet the green light on “output” is not lighting up on the Echoboy, the green light on Input is however, as if sound is going into it. The un-processed sounds are coming out as normal… so they normal signal just with out the delay processing from echoboy.

This is completely new to this version of Cubase. Never had this issue in my entire life up til now. Happens in multiple projects.

win10 64

Would Love to know how to fix this! Sometime it will randomly fix itself and all instance of Echoboy will suddenly start working again, otherwise I have to open a new instance and readjust the settings for it to work. BUT whenever I do that, save the project, open it again - they all break again! so irritating.