I also have a deaf rescue dog, an Australian Shepherd. She's considered a "lethal white" which I think is a pretty horrible name for something so sweet and loving and smart. She's deaf because she was a result of breeding two aussies of the blue merle coloring that sometimes results in an all white dog. Often these all white dogs are blind, deaf or both. Luckily she's just blind, but otherwise completely healthy and happy. A lot of puppies in her position would have been put down as a baby because they aren't easily sold.
I try to tell people about how awesome and normal she is all of the time so that others will be okay with adopting deaf rescues. Because, unfortunately, a lot of them are euthanized, even as puppies by breeders.