After further troubleshooting I've narrowed it down to the automation recording for only a few seconds then stopping (the audio is still being captured though):
Then once it's stopped, it may not start ever again until I close and reopen Sonar fresh, and then maybe I get a few seconds of capture before the same thing again. VERY frustrating.
Here's my automation settings within Amplitube just so you know I'm not a putz: