Sound drops from a track when moving plugins

Hi all,

I have an issue that started with Cubase 7.5 (I upgraded to 8.0 on day one).

very oftenly when I move a plugin from a position to another or activate it, it completely stops the sound from coming out of a track. I can still see the signal (see attached file, but the track where it is routed sees nothing coming in.

Nothing helps (removing plugins, routing it elsewhere, etc.) apart from restarting cubase!

Any ideas welcome!