I have just come across what is definitely a bug in Cubase 8.0.30. It is a fairly complex to explain one that needs images etc, so would be easier to divert you to another post where I discussed it which can be found here:
I have also verified this is a plugin by creating the same thing 3 times. I deleted first 2 templates as I assumed I had got lost in the routing and started from scratch again. However, the 3rd time I realised it’s a bug in Cubase as when I closed to retest my routing and then reopened, the template worked. I have tried again and it’s the exact same behaviour. Once the template is set, no audio can be heard. Once Cubase is closed and then the template reopened, then it works as it should. I have also tried reopening up to 8 times after the initial closing down and it works fine each time after reopening. Therefore, could be a bug causing many headaches for people who use Cubase to score and think the routing on their template is broken when it is actually not.