switch to a different brand motherboard.
its the way it reads the usb's this board did the same with my phone charging cable whenever i had it pluged in to my case and had to disconect it in order to boot.
That's not a very helpful answer.
I'm currently looking for a solution to this and will post it back here in about an hour!
The best solution I have seen is to use a USB hub to power the keyboard. This problem is new to me but mine does not allow entry to the BIOS and occasionally causes problems with sleep and CPU fan speed. I unplug it with power on and don't see the problem for a while.
Use a rear USB port , I have the wave and I found out the hard way the front USBs just didn't have enough volts for it to work right . pluged in a rear port no problem since.