Of course there will be some delay, but usually ~10ms or under is not a problem.
The cause is not likely your Juno. What soundcard are you using? How's the CPU? Have you tried Cubase forums? I'm actually debating a switch to Cubase as my main DAW so this topic is interest to me.
All said, I'm quite certain it's something you can resolve. It may just take a little time as latency issues tend to do.