Torture test for a TT rig!

@rauliruegas , I assumed the OP was using the correct VTF, bad assumption. Non the less a stiff cartridge in an arm that is too light will pop right out of the groove when the right note comes along. Years ago I made exactly that mistake. The OPs tracking is much better given the added 0.7 grams but that does not mean his arm is set up correctly. The Hi FI News Analog Test Record has excellent resonance tracks. These are not the tracks used for tracking ability or anti skating adjustment. Everyone who wants the best bass performance out of their set up needs to get the vertical resonance frequency down between 8 and 10 Hz. As you add more mass to the tonearm the resonance frequency will drop. Soundsmith's graded screws are a wonderful way to do this. The OP will find that with anti skate and resonance frequencies set correctly he will get even better performance. If you disagree with this paragraph then I am afraid there is no hope for you. Sincerely, Me

Both lewm, atmasphere and Chakster are correct. You have to add mass to get the resonance frequency down to 8 Hz. You cn prove that to yourself with a nickel. Soundsmith makes a very nice set of graded cartridge screws that look very nice. Get the test Record chakster recommended. It has both vertical and horizontal resonance tracks. It is the vertical resonance you want down at 8 Hz. This will fix your problem for sure. I have seen this happen on several occasions for exactly this reason.