Reddit mentions of DuPont Teflon Silicone Lubricant Squeeze Bottle, 4 Oz.

is it microphonics from your cable rubbing on your clothes or something? hold your cable rolled up in one hand away from your body so it cant touch anything, then slowly work your head around and see if it still happens. maybe some sharper movements but not enough to fling your headphones off.
 
if it is in fact your headphones, this stuff here is a lifesaver IMO:
 
https://www.amazon.com/gp/product/B00BCVXUVM/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
 
Make sure you get the red capped eyedropper bottle, NOT the spray cans. now carefully check over your headphones and put a drop or two on any spot where the headphones have mechanical movement. Rotating earcup pivots, adjustable headband, any spots that can possibly move. drip in a bit of lube, work the headphones back and forth, then wipe off any excess. My Fidelio X2 were creaking like crazy and now they are silent.
 
EDIT: since you now have way more silicone lubricant than you will EVER use on just headphones, go around your house and check every single moving object. door hinges, knobs, cuboards, drawers. anything that moves, put a little lube on it, and also tighten it all up with a screwdriver at the same time. so many minor annoyances that are never enough to deal with when you notice, all gone.

They were much cheaper on eBay (less quantity), but here's the links for Amazon:

Krytox GPL 205

Krytox GPL 105

Dupont Teflon Si

And I can't find the Victorinox on Amazon

This will be your savior:

• http://www.amazon.com/Chemicals-RUBBER-RENUE-125ML-LIQID/dp/B00LVL3Z3Q
  
  Alcohol drys out belts and the thought of lubricating belts makes repair techs cry. You don't want us to cry do you?
  
  Edit must have misread, you are lubing the gear assembly. You want this this:
  
  
• http://www.amazon.com/DuPont-Teflon-Silicone-Lubricant-Squeeze/dp/B00BCVXUVM/
  
  Don't use something like 3-in-1 or any or the regular stuff you would find in the hardware store. It has too high viscosity and gunks everything up and is impossible to clean off. This stuff is very light and contains teflon suspended in it so it makes everything super smooth without leaving more than a thin coating behind which doesn't gunk.

I highly recommend Hako Clears.

The tactile bump is very clear and high, giving a topre-like feel and a nice meaty cushion at the bottom.

I upgraded from cherry browns and it's like night and day, especially after I lubed both the stems (with [finish line extreme flouro teflon grease](Finish Line Extreme Fluoro 100% DuPont Teflon Grease, 20g Syringe https://www.amazon.com/dp/B002L5UL92/ref=cm_sw_r_cp_apa_i_0TYtDb4EZ5ED3)) and the springs (with [dupont silicone lubricant](DuPont Teflon Silicone Lubricant Squeeze Bottle, 4 Oz. https://www.amazon.com/dp/B00BCVXUVM/ref=cm_sw_r_cp_apa_i_ESYtDbT85X5A5)).

The extra work is 100% recommended for the smoothest tactile action I've ever felt.

Seems like a general issue with the rg unicorn kits. I highly recommend using this lube to grease up the joints. Fixed the issue for me

Not a bad idea, I do get a noticeable sound sometimes that is less than present, but nothing earth shattering. Is there a recommended oil beyond, say, WD-40? Should I do this to the threaded rods of the Z as well?

EDIT: Did some searching and bought this stuff as I found a number of threads saying not to use WD-40 like I initially thought..

I just found that this lube is cheaper than the super lube, and pretty widely used. As for the stabilizers, this stuff seems pretty good.