Plating on SS303

We are into gold plating for electronic application by barrel plating and we are facing severe corrosion problems over a period of time - maybe after a few days or weeks or months.Our base material is SS303 and we give undercoat of 4-5 micron Nickel ( spec is 2.5 micron )above which 0.7 micron of Gold is plated.We are unable to increase Nickel thickness due to dimensional restrictions.Our barrel is loaded up to 60% maximum.We have taken no. of trials including semi-bright Nickel , electroless nickel , sulphamate nickel , change in precleaning proceses , change in composition of Wood's Nickel strike ( our's is 240 : 130 - Nickel chloride : HCl), sulphamate Nickel strike and on an average we do 2 trials per day to fix this problem of corrosion.We have observed that we are not getting proper coverage of Wood's nickel in barrel plating.Can somebody pl. help me to resolve this issue and maybe by experience pinpoint as to where the rootcause lay ?

Thanks and Regards ,