External FX problem/loop - notworking

Hi everybody. I hope someone can tell me the solution to my next problem.

It seems that I can’t get “external fx” to use in Wavelab 10,0,20 (build 97) and is giving me a feedback-loop when enabling the “external fx plugin”.

I have a Focusrite Liquid Saffire 56. The routing is done in the Mix Control (and seems to work in Pro Tools, but I don’t want to go back and forth between DAW’s and want to do everything in WL10)

I’m having a similar problem when trying to use External FX. I’m getting a delay and distortion in Wavelab 10.03 but the same settings work fine in Cubase 10.5 while using External FX. Here a video link of the problem. I use the Steinberg UR824 interface.