CX-30 G122 AT Comfort Machine Grey
It is operating in 2cyl mode not only in 6th gear in my CX-30, but low load is a prerequisite. For OP, if your car does have cyclinder deactivation, it is worth to check the energy flow info screen. There you can see whether the car is running in 2 or 4 cyl mode. If your car switches from 4 to 2 cylinders and you immediately experience the issue you know the cause.