I'm running Ableton Live 9.6.2 on a Macbook Pro 2.66 GHz Intel Core 2 Duo, Memory: 8GB 1067 MHz DDR3. OSX 10.8.5 and I acquired a K-Mix when they first came out. I've since updated the firmware, as of writing this message, on 10.4.16. I still cannot get it to perform reliably as an interface without audio breakup issues. Standalone, it's fine.
I've tried everything that i can think of. You name it, i've tried it. At least as far as I can tell, I've exhausted everything on the ableton side and i've even talked with a KMI tech employee who basically told me, after a lot conversation and troubleshooting, my computer is too old. I don't really accept that, but is there a reason I should? The tech told me that with these specs, my computer should be working. And I can't seem to find documentation citing limitations for my hardware...