You might want to try one cleaning with a 1:3 White Vinegar/Deionized Distilled water solution in case the dog's ears are really dirty. But unless the dog has past chronic ear infections, you shouldn't try more than one cleaning per every few weeks. If you have never cleaned your dog's ears, then have a Vet show you how. Too many cleanings might cause problems.

For the most part your 13 yr old dog may just be becoming deaf, and there is not much you can do about it. Work on your doggy sign language hand signals.