Clear CMOS should be enough, reflashing BIOS seems a bit drastic. And those WinBond chips are only rated for 500~1000 full (over)write cycles, lol, so it's not something you can sustain too long unless you want to buy new BIOS chips.
The onboard CR2032 battery might also have to be removed for a minute or so while unplugged (as in, PSU power connectors detached from motherboard) to insure the mobo is "fully unpowered" while clearing CMOS. Obviously a bit of a pain to unplug everything each time you reboot, especially if that battery is buried underneath your GPU card or loops/cables.
I think the bug is too many USB devices being serviced off the internal hub. Maybe their initial (combined) power draw exceeds what the mobo will provide before proper USB enumeration (after WinOS has started, identified all USB controllers, loaded all USB drivers, and initialized them all, which takes time). Especially since the motherboard is already busy surging power through all hardware at startup, the UEFI might only have 100mA available per USB port.
So you need to have CPU cooler plugged into USB, PSU plugged into USB ... I think ideally one plugs into mobo USB port and the other one plugs into (externally-powered) USB hub which is plugged into other mobo USB port, and no other USB devices are connected - unplug those headphones/speakers/whatever - until Windows boots up to desktop. (Rear panel USB ports, keyboard and mouse, should be okay.)
Another solution would be a PCIe adapter card which provides some internal USB headers/ports. I think it would probably solve your issue, although it might not.
And, of course, a dedicated hardware controller device (with its own power, processing logic, and onboard USB controllers/ports) would work. But they aren't cheap.
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