Here is situation update:
As per mail from Jason,
"We tested several Gungnirs to see what the raw DC voltages are before the regulators, and all have 30V before the 24V regulator at 220V in--so, there's plenty of regulation still left even at 220V, which is how the product was designed.
If yours measures differently, then it probably has a bad transformer. I'm copying Alex so he can arrange a return/exchange. You'll need to ship us your Gungnir back, and when it has been dropped off at the shipper and is showing in their tracking system, we'll send a replacement. We'll pay for return shipping by the least cost option that has tracking, up to the cost of shipping it to you in the first place."
I am really appreciate and grateful with such offer from Schiit. Where as these days most of the time with same situation (based on previous experiences) sellers like to shift the undue responsibilities on buyers. I positively hope, my future upgrades will be from Schiit.