So Weird- No Stylus Contact Woofer Pumping with Hana ML and Elac PPA-2

your statement:

Wiring for the tonearm to the preamp was as follows:

• Pin 1- no connection
• Pin 2- + positive
• Pin 3- - negative
• Shell ground- cable shield

is very very confusing.

This tonearm is for custom mono cartridge? For stereo cartridges, 4 color coded pins (same four pins from arm) are:

positive 1

negative 1

positive 2

negative 2

There is no ground pin for cartridge.

My experience is that ground loop hum/electro-magnetic noise has nothing to do with RCA or XLR plugs if ground wire was connected properly.

remember, Tesla proved a long long time ago that electro-magnetic energy could be transform from source (turn table/cartridge) to receiver (phono stage inputs) if no ground shelling to short the energy.

Actually, this phenomenon states a fundamental fact:  electro-magnetic energy broadcasting as waves/Strings not as particles. So the great Einstein could be wrong right here. 

@byang12 The pin 1 ground to tonearm is the only missing piece of the puzzle, however since the tonearm is already grounded to the phono preamp via the external ground wire, I felt that sending the tonearm ground down the left cable, the right cable and the external wire was not a great idea. My assumption at the time was that the tonearm ground lug was most likely connected at the same circuit point as the two pin 1 connections. 

We'll find out latter this week. 

Just to clarify one point, the TT is grounded to the preamp. The question being is it the correct point?

@nrenter I will be addressing the static issue as well, later this week.

In connecting a cartridge in balanced mode, to a balanced phono stage, ground is left to "float".  As you know, the cartridge has no ground connection, per se, except for a very few older designs, like (I think) old Decca cartridges, and those cannot be hooked up for balanced drive. The shield on the phono cable itself, if there is one, can be attached to phono stage ground lug, but I have three TTs operating in fully balanced mode, and in no case has it been necessary to ground anything to anything. I don't see any problem with Mitchell's wiring scheme, certainly not one that can account for the phenomenon. And it's not confusing.

Someone else very early on mentioned the Hall Sensor, which is very likely used in the drive system of the Yamaha, because it has a DC coreless motor.  On my Kenwood L07D, also coreless and also DC, the Hall Sensor is fixed to the plinth surface under the platter, but there must also be a signalling device built on the underside of the platter itself that rotates with the platter and triggers the sensor if there is a speed error.  It seems possible that in balanced mode the phono stage is picking up a signal from the cartridge, as the Hall component that is fastened to the platter rotates under the cartridge. This is causing an impulse from the cartridge to push the woofer in concert with TT speed.  But why this happens only with platter mat and LP in place, I do not know.

One idea why the problem only occurs in balanced and not in SE mode might be that in the latter case, both channels ARE connected to audio ground, so maybe the signal never gets to be amplified to drive the woofers.  It would be interesting to hook the output to a 'scope and see if one can detect the spurious signal on hot or ground in SE mode.