I have 3 cats, 4 litter boxes. Haven't changed litter at all. My boy cat will only poop in one spot. On the floor next to the basement door. We have had the litter box there before and when he started pooping next to it, we moved it and it sropped for a few days and started back up. I bought a bigger box, didn't help, changed the amount of litter, didn't work, bought the sestressers you plug in the wall, didnt help, talked to the vet, no help... The only thing I can come up with it one of my girls isn't 100% keen with him. They can eat, sleep, play next to each other but as soon as he gets in her bubble, she hisses and swats. We didnt have this pooping issue until about 4 weeks ago. Any suggestions!???