Need help finding litter

I have an 8 year old neutered little sh*t (I'm annoyed at him, so that's his name right now). He started getting claw infections once or twice a year a couple years ago. I want to try and minimize this so I figured I could switch his litter and hopefully they would stop, if not become more infrequent. I've never lived with a cat that gets so many claw infections. Or any, really.

I asked his vet what he suggests for litter and he said pine. So I do that. Now the little sh*t is starting to sh*t on the floor next to the box (although he seemed to be fine for the first few days with this litter(!)). Anyone else have another suggestion that is not crystal litter?