I've had this problem for a long time and I have yet to find a solution for it. Whenever I boot FreeBSD, I can use the bootloader (F1, F2 keys) fine, but I can't use the keyboard during the menu selection (the numbered items). Then, when it times out and goes to the first option, the keyboard is fine. I have USB legacy enabled in the BIOS, but is there a reason why it refuses to recognize a USB keyboard on the menu screen?