You have described the distortion problem I have been working on for some time now, although yours sounds more severe. Mine was with high pitched, high amplitude vocal "air", mostly female, but piano was ok. I have the DV XX2 MK2 and also use the Mint tractor. The problem turned out to be the distance from the spindle to the tonearm pivot was off a little. A very tiny little. Because of that the Mint Tractor made me align, very precisely, to the wrong arc and overhang. I used the VPI jig that came with the arm to reset the distance. After realigning the cart with the Mint the distortion was eliminated and replaced by incredible detail. Double wow! I had tried everything I could think of for months on end. The DV carts have a well deserved reputation of being sensitive to setup error. Good luck!
Bill
Bill