I haven't. Seems to be working fine most of the time now. Co worker welded up a stand and most welds were fine with exception of a couple started good but changed part way through. We changed the cone on the lead. The one we had on seamed a tad short. The tip was sticking out a touch. But I don't think that did anything. Hopefully new orings will fix it.Have you guys looked into your ground?
A look at the cable going into the lug in your clamp.