I am not familiar with your specific hub, but metal chipping like that is usually caused by high force impact such that can occur by shifting under power. We have damaged a Spinergy hub and several cassettes over the years by doing this. We have had to change our shifting behavior for these scenarios by shifting in advance of when we might normally and limiting to multiple single shifts rather than multiple. Again, just for the scenarios where we’re under a power stroke where the chain can skip when jumping gears.