There are a couple of drawbacks to OSP from an assembly standpoint One is that we would get occasional "busts" where the solderability of the pads was poor on a few pads on the board. The other area where OSP can fail is with via in pad (VIP) product. If there is any residue remaining in the holes it will cause a degradation of the OSP coating. determine to not be the OSP process at fault, but rather things like unseen soldermask residues or incomplete removal of the tin etch resist. Doug, this seems to be a problem with your board manufactures control of the process. regards Rich Fudalewski FCT