Hi do you mean that below the jumpers are soldering bridges or do you mean on the bottom side of the board?
Concerning the whining, to me it looks more like the motor is stopped between two full steps as the whining is only present on certain axis positions.
I correctly identified the two phases by shortening two of them. I also used two identical motors and connected the same cables together, then when I turn one by hand slowly, the other turns as well. But when i turn one two fast the other starts to show similar symptoms as when driven by the Ramps Board.
Concerning the whining, to me it looks more like the motor is stopped between two full steps as the whining is only present on certain axis positions.
I correctly identified the two phases by shortening two of them. I also used two identical motors and connected the same cables together, then when I turn one by hand slowly, the other turns as well. But when i turn one two fast the other starts to show similar symptoms as when driven by the Ramps Board.