The entire Tonearm is not aluminum, nor stainless-steel it is Bead Plasted for a Matte Finish, then Industrial Hard-Chromed. If it was touched with sweaty fingers & not wiped off during high humidity and the table covered it will rust in time. Industrial Hard Chroming is to be able to withstand 500-2000 hours of salt-air exposure in a ventilated enviorment. However in a non-ventilated it will pit/brown in a matter of 48-72 hours. Call VPI see if they had any other reports, as I'm sure they have them done by a sub contracted outside facility. It may have been a bad chroming batch they received, & VPI quality control will not spot it till it fails by the end user. I too am a VPI owner, however I have no issues with my arms finish. Do not use WD-40 as it attracts dust, & you don't want to take the chance of getting any type of lubicating fluid near your Cartridge. Good Luck!