The Chase drive will act up; jittering, stuttering, jerking, etc., if it cannot keep up with your demands (possibly refusing to work at all if left uncorrected). It will continue to jerk and jitter even with the line off. When this happens you will need to "power cycle" the drive before it will work properly.
POWER CYCLE STEPS
1) Start with the drive having been unplugged for at least 3 minutes (this will allow sufficient time for the capacitor to completely discharge)
2) Then plug the drive in
3) Press and hold the pairing button paring button on device until the blue light goes off and comes back on again
4) Try using the app to move the motor in both directions
This should stop the jittering behavior - (you may need to try it a couple of times)
But you also must fix the cause - which means making adjustments to the course. If after making adjustments, it begins to jerk and jitter again you need to repeat the adjustments and power cycle again - until you can get the drive to successfully run without being overtaxed.
See: Chase motor acting up? for tips on adjusting the course.