I am using a VPI 10.5i with a Benz Ebony cartridge, so what I tell you is good only for this installation and may or may not work for you. I find that just a bit of damping improves the cartridge by making it more transparent with improved depth, width and focus. If I use too much, the cartridge sounds dead and sloppy. I think you should try damping - you can always remove it with a toothpick or Q-tip. Nothing ventured, nothing .....
You can get damping fluid from VPI.
You can get damping fluid from VPI.