Check to see if you have twisted the wire that runs from the arm to the locking collet. Even a slight twist will create a very large bias force that will cause this.
It is probably exacerbated by the mismatch between the low compliance cartridge and the low arm mass. This is not a good match at all.
It is probably exacerbated by the mismatch between the low compliance cartridge and the low arm mass. This is not a good match at all.