Hi newbie here

, I will be collecting a rescued 8+ yorkie male at the weekend and have been told he is deaf.
Any ideas what could have caused this?. As far as I know no vet has looked into his ears. Do yorkies have to have some hairs removed from their ears sometimes?. Seems to ring a bell.
BTW Ive had rescued dogs for over 43 yrs, but never a yorkie.