ps/2 keyboard problem.

[MustangSVT]

i am using an older keyboard that doesnt use ps/2 plug on my BH6 mb with an adaptor.
most of the time it works fine, but sometimes i have no responds at all from keyboard. it doesnt just die out or anything if it was working, sometimes it does not work after booting. However rebooting will fix the problem..

this only happens like once in awhile so its no big deal, but any idea why its doing that? is there any settings in a bios that might fix this problem? thanx.