Tinnitus or ringing in ears is a condition in which a person hears sounds like ringing, whistling, buzzing, chirping or hissing without the presence of an actual source of these sounds (external stimuli). The sound may be soft or loud and of a high or low pitch. Millions of people in the world suffer from this condition. Tinnitus can occur due to various reasons that include excessive use of earphones, build-up of earwax, ear infections, thyroid problems and even cardiovascular diseases.

https://apnews.com/press-release/ts-newswire/business-corporate-news-stress-north-america-mental-health-6baa4dfdf29f92d1a2781c598fca4fba