I developed tinnitus a year ago (I'm in my early 30s). I was living in an environment where it was noisy in the morning so I took to wearing sound cancelling headphones and earplugs to sleep.

A few weeks into it I noticed a persistent ringing and I thought it was some sort of electrical wine in an old house. A week later I realized it was permanent so I cut out my sound cancelling sleep routine, but the tinnitus has stayed.