This looks like the right answer to me.
To the OP...
do us a favor and screw your Russian 91% V2 on your black box, but only enough that the center pin "just" makes contact with the center pin.
Let us know what the results are.
I am betting that this is the reason for the issue.
The problems that people are experiencing is not with the V1 as pictured, the problems are existing in the V2 Russian which has a spring loaded center pin in place of the one you see in the posted picture.
It looks like this:
