I am not allowed to change my cats litter or change the litter box. If I do, I get poo balls tucked around the house. It has to be unscented scoopaway, and absolutely no roof on the privey. I pay, right away if I deviate. Your spoiled feline may be trying to tell you about the litter condition, or about some other change that is unacceptable. It may be apparent if you think about when the problem started. If this won't work, a trip to the vet is also a great idea, as your kitty might be trying to tell you that something hurts. Clean up your spots with white vinegar only as soap and water encourages revisiting a spot. Good luck and keep trying. Also, you may want to check out Feliway. It uses pheromones to retrain kitties to not spray.