We had a situation like this a while ago. My wife likes to rescue cats, and one time she rescued a liter that was abandoned (they were only 3 days old). Long story short we nursed them and they became playful, like chewing on the cords of 2 Razr mice, 2 backup mice, computer surround system, baracuda headphones, etc. etc. After ensuring the kittens safety, she went looking, come to find out hot stuff like chili pepper or such, most of the time doesn't work. Get something bitter. (sometimes that doesn't work but not often) We used lime juice on the surviving equipment and hadn't had a problem since with any litter.
