I would check with VPI and see what they think of the effective mass/mechanical resonance issues with regards to playing that cartridge in your arm.
The mechanical resonance should be between 7 and 12 Hz, if its off, you can get crazy woofer pumping. The way you describe it, this problem did not show up until you got the table setup done recently- that really points to the arm/cartridge compatibility issue.
The mechanical resonance should be between 7 and 12 Hz, if its off, you can get crazy woofer pumping. The way you describe it, this problem did not show up until you got the table setup done recently- that really points to the arm/cartridge compatibility issue.