If your plugs aren't making good contact with the battery, it would cause the same thing.

I don't think these nano-tech saddles like high discharge. Me and a mate are both running nano tech saddles in durango 4x4 short course trucks with tekin RX8 esc and tekin pro4 4000kv motors and the same gearing. He has the current limiter set really high (around 95% or so) and he also has a very heavy trigger finger. His batteries used to be unbalanced a fair bit (about 0.2V - 0.3V difference between cells) after doing a 7 minute race. He had 3 saddle packs, and it happened on all of them.

I, on the other hand, run a current limit of 60% and I'm reasonably smooth on the throttle. My packs never differ by more than 0.03V after a race.

He's now gone to Orion packs, and hasn't had the problem again.