The phrase "tin ear" means someone who has difficulty understanding or appreciating music or sounds. It refers to a person's lack of ability to recognize tone, rhythm, or melody. Full definition
While original writer James Toback grounded his 70s script in autobiography (he was both teacher and gambler), Monahan exhibits an uncharacteristic tin ear for the film's wordy milieu, leaving the cast (including a sorely served Brie Larson) to wrestle with toe - curling am - dram speeches about the nature of life, love and learning. (theguardian.com)
Reuters ended its story with another hostile quote from a critic who called Benedict's pontificate a «tin ear papacy,» adding. (firstthings.com)
In any case, the term's real tin ear comes in its inability to understand that personal characteristics, over which we have no control, should always be kept out of political discourse, even insults. (theconversation.com)