Remedy for my Cat's Ears

I was wondering if someone could suggest a natural remedy for my cat's ears. There's no infection or anything like that as far as I know, but his ears are sensitive and it seems like sometimes they itch on the inside or bother him somehow from the way he acts. He doesn't like anyone touching them.
I used to give him something from the vet to keep the ears clean for a while and I think it's been since then that he's had this problem. I don't give it to him anymore.
Thanks.