TC going crazy on my 05 Suburban

Seems to be getting worse too. If I'm at a stoplight for a normal light cycle, when I slowly accelerate, the TC kicks in right away for about 3 secs, then goes away. Happens in high grip situations with very little throttle. Started a few months ago, but only the "pump" would cycle for a few secs. Now, occasionally, it'll really kick in (dash read out lights up and the car slows). Doesn't do this if I turn off the system.

Is there a known cause for this, or do I need the dealer to run a diagnostics on the system to find the error? Thanks