I mostly hear 'tin' from women who tend to lisp slightly on the "kwess" and it literally comes out sounding like "kwess-tin." I hear this all the time IRL and on TV. I was hoping to find out if other people notice this or not, but damn, y'all hyper fixated on me writing "tin." Anyway, it has always seemed odd to me since the way I say it does sound closer to kwesh-tin, kwess-chin, or kwess-chun.