well according to earlier post of DC overload, it sounds like half the DC'S S7's could be fried ;\
hence some are getting fine hash and others having your scenario.
it was a great group buy, but mining went insane last 4 months+ , and Li, tho a great guy, mismanaged it into a hole ;\
cut your losses, this is the risk of mining, sell while you can , S9 will HOPEFULLY be soon. (tho BMT's shody machines are not meant for the conditions these were in they are seriously cheap chinese crap)

~Lesson Learned~