Is there a way to use mix of outputs of interface instead of separate channels?

[fivebeforechaos@gmail.com]

I have a rather large setup, as I use a lot of synths, and generally, it ends up coming to about 10 stereo channels or so. Is there a way to have it so that Jamkazam will just take the output of my sound interface instead of sending out the individual channels? I think that would make a huge difference, in terms of bandwidth. It's not feasible for me to use a mixer at this point, because I can't afford one that would handle everything, at this point. I have my levels mixed properly with my interface's software mixer. Another reason this would be useful is that I don't always use all of the channels, but want to have them available if I do, so that's more bandwidth being wasted. 

If I can't do this, it would probably be best to just put an option in such as "use monitor output from interface". 

Thoughts?