I just re-read your post there. So you were in full step mode with a VRef of 0.7v and you measured 0.65A input to the motor coil?
That’s off by a bit alright. In full-step mode you should be getting 70% of the current limit. That’d be (0.7v x 2)x0.7=0.98A
Now saying that, nothing about this process is stable so the current and voltage will be changing all the time. I’m not sure how that would affect the reading you’re getting. Did you measure the current while the motor was moving or while it was holding position?
I can’t test my own to verify for you yet because I’m still waiting on my DRV8825’s to arrive. I’m just using some A4988’s that I had lying around to test my setup until they get here.
Once they show up though I’ll gladly test it to see if I’m finding similar readings.