About six months ago I was given a SoundBlaster Live! sound card which, I knew, had been used by a guitar playing enthusiast...:-)
I was told that the line in socket was probably kaphut as a result but, to my amazement, it still works perfectly with various device inputs.
Personal thought was that it would have been overloaded signal wise using it with a guitar but obviously not the case.
These guitar recording links should prove helpful: