Tuner plug in

I’ve been working with Cubase 6.5 for like six months now and I’ll be darned if I can figure out how to get the tuner plug in to work. It would be way convenient to have it functioning as I record lots of acoustic guitars that need frequent tuning. Is there some secret to it that I’m not getting?

Is there some secret to it that I’m not getting?

No

Direct monitoring on? if so turn it off!

That did it. So there is a secret! Thanks.