Welcome to the most and least concerned mother board issue , which is merely only 30 affected out of millions , as per Asus. No matter, the affected count increases ,they will tell only 30 and it's negligible.
Well since it's been only 2 days you can file for replacement. You're lucky you bought the phone so late. The people who bought on the first week of launch (literally the first second of launch for me. I must have one of the earliest to order this phone) got to know that their phones are faulty after the replacement period was over.