There is a bug in certain versions of OSX 10.9 that prevent the OS from properly naming the K-Mix. You can fix this with a bit of tinkering in your Audio MIDI Setup.

1. Navigate to your Audio MIDI setup by searching for it via Spotlight (cmd + spacebar), and connect your K-Mix.
2. Find the “USB Audio Device” icon, unplug your K-Mix and delete the icon.
3. Plug in your K-Mix and hit ‘Rescan for devices’. You should see USB Audio Deivce again.
4. Unplug your K-Mix and delete the icon.
5. Go to the Configuration menu and create a new configuration.
6. Plug your K-Mix in, and a USB Audio Device should appear. \
7. Unplug your K-Mix, delete the icon and naviagate back to the original configuration.
8. Plug your K-Mix in and it should appear as K-Mix.
9. You can now connect to the Editor!