Had a lot more success when turning the buffer way to the right at around 470 samples, latency seems ok. But now this problem. I have a ticket in to NI support:
I connect the RK2 via USB. I go to system prefs and set the audio in and out to the RK2. I launch Ableton Live. I set the audio ins and outs to RK2. I plug my headphones into the headphone jack of the RK2 and set the levels at about halfway. I load up GR2 as a plug in and play. Everything is fine for a while, but eventually the sound through the headphones just stops. I can't hear anything from any of my tracks and there is no input going to the GR2 plug-in all of a sudden. I can see the light on the RK2 responding so it's receiving signal from my guitar, but there's no input to GR2 and absolutely no sound through my headphones from GR2 or any of the other tracks. Deleting and reloading the plug has no effect. Quitting out and restarting Live has no effect. The only thing that seems to help is rebooting the machine and starting over, then I'll get another 3-4 minutes of being able to use GR2 and RK2 again before having to repeat this cycle.