Diplacusis

Same sound heard differently in each ear, a pitch mismatch

Overview

Following hearing loss, one ear may perceive a given tone at a different pitch than the other, so a single note sounds dissonant or doubled. It follows sudden hearing loss, Meniere, noise damage, or ear infection, and typically appears during or after the insult. Musicians notice it most painfully, instruments sound out of tune. It often improves as the underlying cause stabilizes. Hearing aids that restore symmetry reduce it for some. Its presence indicates cochlear dysfunction, usually outer hair cell damage.