Rrealy don't know why somes guys have this problem and other don't
The only thing i can suspect, is the LVC on somes MGM version that are different, maybe set at 3.2 to the place of 3.1, and with cheaper li-po pack, the LVC kick in sooner.

But with high end pack like Flightpower, i suspect that the problem will be present when the batterie will be at half of the capacity