By writing a really annoying full page letter. Seriously. I tried to adequately convey the fact that I think the fit is very VERY close, but that the tiny problem is just annoying enough to make them uncomfortable. I described the location of the discomfort in detail (feels like the very end of the right earpiece is too deep in the canal). I then took a very thin piece of scotch tape, colored it with red sharpie, and placed the tape around what I perceive to be the problem area.