i wonder if you got a miss labeled S17 pro, it runs at 50 TH for normal mode - does it have turbo mode option? If not, I would be in contact with Bitmain - 6 TH is a bit of a variance, too big to overlook in my opinion.
and if you did get a S17pro - I would be asking for some money back as its about 75 USD cheaper.
Nope standard S17 56th unit, it appears bitmains auto-tune function is broken because my my first 2 hashboards are avg 18000gh each and board #3 is averaging 12000gh and I only have Normal and Low Power, no turbo.