Which side draws more current?

[turbo4]

I'm using thunder power pro packs (30c). These are new packs. If the ESC is looking at total voltage then how is it cutting of at xx volts per cell? I have mine set at 3.2v per cell, however I had one cell get to 3.08. I did run the truck until the cutoff. I did not notice a stutter, but It would stop altogether if I gave it full throttle. Every time I go to charge the packs one pack is always less voltage than the other. I have not kept track of if it is the same pack each time, I just figured that one side was driving the servos or something.