My cat Thunder who is about 1 1/2 years old has be going to the bathroom outside his litter box for the past couple of weeks, specifically on my couch and bed. His stool is loose at times but I don't notice any blood. He also eats and plays just fine. He is on Acana dry food. I have had the problem before and had taken him to the vet and they couldn't find anything wrong. I have stared him on probiotics about 5 days ago and so far haven't noticed any difference.