The sound of people chewing, slurping, tapping, or humming can drive some people into a rage, and scientists have actually discovered the neurological wiring responsible for this strange condition.
Called misophonia, it describes the unreasonable emotions that well up in some of us when we hear certain repetitive noises being produced by other humans. People with this condition experience annoyance or even anger at the clacking of a keyboard, the rustling of a chip packet, or the smacking of lips.
While it's been recognised as a condition since 2000, research into the cause and prevalence of misophonia has been limited. There are no official criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), and those who experience it often find it difficult to be taken seriously.
But a study published in the Journal of Clinical Psychology in 2014 suggested that misophonia could affect as much as 20 percent of the population; a 2015 study in Australasian Psychiatry argued that it was associated with obsessive compulsive disorder and anxiety, and could potentially be considered a disorder in its own right.
While we all might feel a twinge of bother, having misophonia turns an annoying sound into an enraging experience, as it spreads through different parts of the brain associated with 'fight or flight' responses.
Research team lead Sukhbinder Kumar described the impact of their 2017 discovery: "For many people with misophonia, this will come as welcome news, as for the first time, we have demonstrated a difference in brain structure and function in sufferers."
Sadly for those with misophonia, the discovery doesn't come with an easy fix. It might help the rest of us sympathise, however, and consider chewing with our mouths closed.