RiseFall123
100+ Head-Fier
I have all of the exact same behavior as you. I haven't gotten the new one back but the dealer assures me it's from newest stock just in for the holiday so we'll see - if it has the same behavior I'll return the unit for a full refund.
Do you remember the beginning of your serial?
I also ask to my seller some days more to return it in order to understand better the situation.
If the issue is only the loud whining in the last 6 minutes of a full charge, I could live with it. Probably.