James,
I have same problem of my console shutting off while playing games. The console just turns off with no warning. There is no message saying the console has overheated. I keep it on the top of my desk in a very clean and well ventilated area and I dust it out routinely. It happens specifically with emulated games or games that were originally released for the Xbox One. The games that it happens with the most are EA games like Battlefield 1, Battlefield V, Titanfall 2. It also happens on old games like Splinter Cell Chaos Theory and Red Dead Redemption 1. Weirdly though it DOES NOT happen on much more demanding game like Hell Let Loose and Red Redemption 2. I have played dozens and dozens of hours of those games and Halo MCC with no shut offs.
I have looked through similar reddit posts and xbox support with similar issues and tried absolutely everything that was suggested (including what microsoft support reps said to do).
I have tried
''-Complete console reset''
''-Plugging console directly into the outlet''
-''Changing power settings to no auto shutdown''
''-Changing outlets''
''-Cleaning console (had done professionally)''
''-Replacing thermal paste ( had done professionally, Console works just stills shuts down in same way)''From what I can gather online it
I did end up replacing the power supply and it did not fix my problem, at this point I am out of ideas.