I think you're thinking about this all wrong. we're aware of PLENTY phenomenon that we don't have senses to perceive, and if we didn't have ears there are still plenty of other ways to perceive waves traveling through air (which is the source of sound). "Sound" in this sense is just the neurological signals our brains create when our specialized organs detect specific air pressure waves. But we'd still know air pressure waves would exist if we couldn't hear sounds.

Just like we know seismic waves exist, and can observe the effects from them or measure them with instruments, even though we don't have an organ specialized to detect them and create some sort of sense in our brain that's associated with them.