I just received K-Mix and upgraded the firmware to 1.3.5. I also posted some initial thoughts on https://www.thegearpage.net/board/index.php?threads/keith-mcmillen-k-mix.1841228/.
I'm connected to iMac macOS Sierra 10.12.5
Currently it looks like all audio from the computer, e.g. audio from Youtube via Safari, music from iTunes, all get routed to the master fader, which then go out to the monitors. Is there a way to route different audio source to different channels before sending out to master? For example, I would love to route iTunes to channel 1, Safari to channel 2, etc. so I can independently control their volume. This would be great. Thanks.