Kinetic Customer Shipment Entry duplicating lines sporadically

Has anyone run across the Kinetic Customer Shipment Entry sporadically duplicating lines? We have a user who is seeing this but we cannot recreate it and cannot pinpoint what could be the cause. They use the “New Line” icon on the Line Details to add new lines - pulling in the line detail by using the search in the Line box and then making some updates before saving.

I was able to recreate lines duplicating when adding them from the Shipment Lines Grid by tabbing quickly through the columns on a new line but this is not where the user is seeing the issue.