Now how about buying atm vxx put vxx is @ 41.20 so looking at oct 41 put trading at 2.55. This order increases my initial margin by $232. Try it with any other option like spy and you will see 0 increase in initial margin.
So this is the problem, there is no tail risk or any kind of exposure, outright buys are margined @ 200% for etns and ~100% for options. Its an error I am sure, but their customer service process is too broken to get this through to the right people. I really hate moving, I love their API and lot of other stuff, but this new margin and the fact that it now changes daily is just killing any other benefit they might have over other places.