Why can't I see all my cymbals in the mixer?

When I go to the mixer tab in Groove Agent, I can see my ride, crashes, china, splash, but no hi hat! I really need to change the output of the hi hat but I can’t get the mixer to show more than six cymbals!

Prompt help would be appreciated, got an active project here!

You will find the Hihat mixer channel by selecting the “Groups”- tab .