My daughter has a Challenge 15MP. Sometimes when she returns the carriage to the feedboard, the gears “chatter,” that is, the gears are not matching up and it makes the carriage shake. I’ve looked at it and don’t see anything obviously wrong. I did note that she does not turn the power inking off when printing, so the roller gear engages the power inking each time she returns the carriage to the feedboard. Is the problem as simple as she should not leave the power on, but rather cut the power on once the carriage is at the feedboard?