Occasionally, the touchpads may make noises and go off by themselves, but the Hub is programmed to re-calibrate them back to normal after a puzzle has been completed. You can also try these tips in the following order to help alleviate the behavior:
Place the Hub flat on carpet, linoleum, or wood floor. If the Hub moves from one surface to another while it is plugged in, this can cause the touchpads to recalibrate incorrectly.
Wipe the touchpads clean of excess slobber.
Unplug the Hub, and plug it back in!
Your touchpads should re-calibrate and return to normal.