Xbox Series X - Turning off after powering on

Hi

Posting here about an issue that is happening with my brand new Series X

Occurring randomly, without a pattern... Might happen today and never happen during the upcoming days, or just happen every day.

- I turn the console on...and after some seconds (maybe 10s) it turns off.

- I try again , this time powering directly through console power button.. It stays on for some seconds ...and then, puff... Off again.

This repeats multiple times, or just once or twice. There will be an occurrence where the console stays on and it doesn't power off. Then I'm able to play, for hours.

I can't say that it's an overheating problem, I mean it's a cold start.

What I have done so far:

- replaced power cord

- tried with different HDMI cable

- tested different monitors

- another wireless controller

- factory reset

- changed power modes

Nothing seems to do the trick here.

This is really ackward. It feels like something wrong with the MB or BIOS.

I'm going to send my emaculated unit OFR, but I'm afraid it will become a dead loop. I have seen multiple users sending their consoles for repair due to this problem and they still report that the issue re-occurs from time to time.

:)