Possibly the two phono cartridges differ in the degree to which the body and/or the cantilever of the cartridge is grounded, thereby making one of them more likely to dissipate static charge vs the other. I agree with Geoff that the rubbing of the stylus against the vinyl has been shown NOT to be a major cause of static electricity build-up, but charge can be removed by devices that are in a way similar to a cartridge.