I dunno about burn in for Trinity products.I had an issue with my Master where the left side volume was lower. After extensive testing and A/B-ing with various devices Jake asked me to test them again. After that I had to send them back for repair, at my cost. About a month later I received a repair/replacement. The new set had a strange issue where the right side seemed to have a loss of resolution. Hi-hats & cymbals were noticeably less punchy on the right side. After emailing Jake he asked me to try burning them in for ~100 hours. Sure enough this worked, but it has left me feeling less than enthusiastic about the whole situation. But I guess burn-in isn't a myth.
My Vyrus V1 sounds same as it did in June 2016 about 1 year ago.
But burn-in can exist to some and some not. I do not doubt you might have experienced burn in.
I have to give props to Jake for fixing the iems or replacing them.
But I also Read this from an article though
I dunno kinda interesting to read.
"Shure has tested some thoroughly used pairs of its E1 earphones, which first launched in 1997. And guess what? They measure the same now as when they came off the line. In fact, during the 15 years Shure has been actively selling earphones, its engineers have reached the same conclusion again and again: The sound produced by these tiny transducers during final testing is the same sound you'll get in a day, in a year, and in five years... unless something goes wrong."