I assume you will be replacing the underpowered controller in the next batch also?
can you give us details on this ? only reason I ask, the Bitmain tech is asking me to switch boards from one of my working miners .
Ckolivas was quoted a few pages back about it:
It turns out the controller is so low powered that it can only process ~30 shares per second which mean that unless diff is set higher, they work their way into a death spiral before diff catches up. Great...
EDIT: Which
presumably means that it can't be fixed by any new firmware releases - it's a hardware issue.