Stringing with Prusa Mini w/ BondTech extruder and Copperhead hot end

Stringing with Prusa Mini w/ BondTech extruder and Copperhead hot end

I went all in with the upgrades for my Mini.  I can print filaments now that I couldn't print before.  The print quality is over the top.  Mini has never printed this well before.   However...

I have bad stringing that that won't go away. The stringing is very fine strands.    
  1. Using the Vanadium nozzle 
  2. I've used the modified retraction settings for the extruder that I found on the Prusa forum to no avail.  I've parametrically adjusted them and haven't found a combination that led to any  improvement. 
  3. I've tried temperature variations with temperature towers- same results for all temps between 220C and 190C with 3 different filaments.  (yes, makes no sense)
  4. Boot on and boot off - same
  5. Fan 100% or fan 50% - same
  6. Extruder tensions screw - two turns from seat normal then one turn tighter - no effect
  7. Same results with 5 filaments - Prusament PLA, MH Pro PLA, Amolen bi-color PLA, Jessie PLA and Atomic PETG CF.   
  8. Using Prusa Slicer 2.3.0

I'm testing with the "Stringing Test Prusa 3S" stl from the Printables site.      
  
I'm running the latest firmware on the Mini and made the changes in settings per the instructions during installation.  

Am I the only one who is having this problem?  What did I miss?