A speech impediment. I just always thought he spoke completely clearly and without a lisp or anything. I'm greatful to the OP for finally bringing this important issue to our attention. Frankly I'm shocked that it hasn't been talked about on here before. Lou really needs to take care of it. Someone should tell him he speaks differently than everyone else, so a doctor can correct whatever's wrong with him. I just can't believe nobody ever said anything ever about it until just now.