We purchased a Gremsy AEVO gimbal, and after balancing and calibrating the motors and tuning the settings it still has a flicker issue.
Our gimbal is connected via MAVLINK to a computer via USB serial. During operation, when the gimbal is locked to a position, the pitch axis will flick up and down constantly, first flicking away from its setpoint then slowly returning back before flicking again. The yaw axis also appears to occasionally suffer from the same issue, but the magnitude is never nearly as much. It also doesn't appear at all on any axis when the gimbal isn't connected via MAVLINK and isn't locked to a setpoint.
Attached is data from some tests that show the flicker. The data is gathered from the MOUNT_ORIENTATION messages coming from the gimbal, and tests with a laser pointer indicate that these values are very accurate to the mount's actual position.
What is causing this issue?