I can't be absolutely sure what it is, but the likely thing is a loose or dirty connection on the mother board.
If not that, it is a bad I/0 and that requires replacement of the entire board usually.
if you want to get into it, I can help to guide you and keep you from making a booboo. You will need to be able to get the case open.the rest is done with the fingers.
See her case at post #32, be advised.....