Ruing metronome through CueMixes and having a master for cue mixes

I run three headphone mixes, using the Cue Mixes setup in the song portion of the audio setup. Does anyone know how to get a Master Volume control for each cuemix? I'm ruing on Apollo Quad, headphone mix 1, 2 and and aux mix. I can't find a way to have a Master apart from each chael.

Also, getting a metronome to that individual headphone feed. I can find it in the Master out, but I can't see how to get the click to the headphone mixes.

Thanks,

Rich