I enjoyed this one as well. (But Sign has a lot of smut, lol. This one is a bromance and the other title i posted is a Shounen Ai. https://www.mangago.zone/read-manga/nanohana_boys/
I made the hypothesis that you were looking for a story with one of the characters being deaf or having hearing impairement, and a beautiful relationship that we see unfolding _ But maybe you were thinking about another trope, which is someone getting turned on by earing the voice of a specific person ?? I enjoyed that part in Sign, as well. The delivery in Sign was so funny!!
Yay i don't know that one!
Do you know other manga/manhwa like "Sign" ??