Wow! Have had this issue with my swords of fury!
Took minutes at the beginning to be playable, ended up taking hours eventually.

It is not power supply related => rebuilt it with no change.
Did a swap of the MPU with a prisitine one from a big guns => bam, everything solved!

Also changed the U41 before the swap => nothing changed.

Original board has been sent for repair, as it was above my capacities, but it is clearly lying in the MPU.

Good luck, but also interested in knowing what's up here, will cost me less to save the board.

The board had some acid damage when I got it.
Cleaned it, but i clearly can not rule it out as a cause.

Ok, good to knkw. Will try that when my board comes back if they did not manage to find the issue.
Thanks for the feedback!