I successfully did the the soldering mod by bridging the 2 gaps with some 30 gauge wire, and the 5V Fan mod. I am running 12 on a Raspberry Pi using the Hashra image (V1.3.3).  At 850mhz everything works, I have one GS that is really slow to get shares though.  Over the past 11 hours, All theo ther units have gotten about 3200-3300 shares.  This problematic one has only 125.  At 900mhz or 950mhz it and one other unit report as running but wont accept any shares. 

Any ideas why this is happening?  I am kind of unsure how to even figure out which unit this is physically since I don't know where numbering starts on the USB hub or how the Hashra image assigns it.