Matthew 11:13-15 (NIV)
For all the Prophets and the Law prophesied until John. And if you are willing to accept it, he is the Elijah who was to come. Whoever has ears, let them hear.
Here's the trick with reading the bible and considering things in context: You have to keep in mind the time that the bible was written!
Two thousand years ago if a person was deaf, they were deaf. There was nothing that could be done about it: no sign language, no cochlear implants, minimal literacy.
Being deaf back then was a completely debilitating state.
However with "modern" innovations like literacy and sign language, we can actually communicate with people who may not be able to actually hear.
So when we read verses like the one in the question or the one at the top of this answer, they are very literal--for that day and age. However, today we are able to communicate with deaf people as easily as I'm communicating with you right now.
Should we take it literally? Yes and No
The concept is "if someone can hear, they should listen and learn". In today's modern age (ya know, the past few hundred years), there is no reason that deafness excludes someone from salvation.
Just as you, right now, are not hearing my voice (I'm not even speaking!), so you do not need to "hear" literally to be saved.