Sorry, but I don't have a quick and easy answer. Before jumping the 'black pad shark,' tell us more about your boards ... * Is the gold still on the pads after soldering? * Can you make the pads take solder using a soldering iron? * Does this happen to all boards? Or just every so often? * Are all of these boards from a single source? Or are they from multiple suppliers? * What is the 'actual' plating on top of the copper on the boards? * How are the boards packaged from your supplier? * How are boards stored after receipt from the supplier?
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