I have two beautiful chocolate Burmese cats, nearly 2 years old. They are very friendly, affectionate and settled. They are both neutered. One has just started to urinate (twice) on the front door mat. We replaced the mat immediately - but both had rubber backs which I read can imitate the smell of ammonia and he might think it was somewhere to urinate. Two questions - I have wiped tiles with a weak white vinegar solution - it is only this area - what can I do/spray to stop him doing it again?