+1 :wink:

Could be since that one pack has a weak cell, so once balanced, the pack with the weak cell will have say 4.05volts per cell whereas the other pack is very well matched and its cells all balance out to 4.20volts. This would cause the discrepancy seen in your packs. best bet is to balancer charge, allow blinky to finish, and then balance charge again so the voltage difference is minimized.

In other words, get a better balancer/charger combo such as a hyperion

If each pack is balanced on the same balancer via Y harness, there should be no difference between each cell once the charge is complete, provided the balancer has time to equalize each cell. Another way to do it would be to charge/balance each pack individually; same result, just would take twice as long.

I too think there is a weak pack so it appears to be discharged further. It could simply be the LVC is set too low and pack1 is on the sharp slope of the downward voltage slope, while pack2 is just reaching the end-of-cycle knee. I would maybe boost the LVC point a tad. 3.2v/cell works fine for me.