Mine isn't stable above 575mhz. If I push it any higher at all I get constant USB disconnects and the hash rate plummets. Have you installed any extra cooling that is helping push the clocks higher?
No, has nothing changed.
My BJ is batch 2, PCB 1.1.
I said out there but I repeat, memory card in the Rpi was unstable, with a piece of cardboard stopped moving and no more problems, so far...