An exquisite characteristic of the auditory system is its ability to sense a large range of sound intensities from whispers to loud alarm sounds, covering 6 orders of magnitude in acoustic pressure. Deficits of sound intensity processing may lead to hearing loss and/or major auditory perception distortions like tinnitus, the perception of phantom sounds, or hyperacusis, a reduced tolerance for moderate sound levels. Audiogenic seizures, reflex seizures induced by loud sounds, are a common feature of many mouse models for central nervous system disorders and may be seen as a model of auditory hyperexcitability. However, the mechanisms underlying these seizures are still poorly understood. They are thought to reflect an imbalance between neuronal excitation and inhibition in the central auditory pathways. Interestingly both peripheral and central hearing impairments, either acquired or congenital, increase the susceptibility to these seizures. Here, we report a genetic mouse model for deafness, which shows a particularly high and sustainable susceptibility over development to audiogenic seizures. Through a screening of these mutant mice and the creation of the corresponding cre fate mapping tool, we identified and characterized a candidate neuronal population in the auditory brainstem with functional deficits, which could account for auditory hyperexcitability in this genetic form of deafness. This model provides new opportunities of deciphering pathophysiological mechanisms of auditory hyperexcitability.