You could rename that file so it won't load when LFS starts. It's located in the lfs/data/sound folder. If LFS can't locate it you will get a small warning and the sound will not work in game.

You could call it something like InvalidKey_.wav until you get your Keyboard sorted out. Then when it's fixed you can rename it back to InvalidKey.wav

Thankyou. I guess you could say this problem has been solved.