Adapting easily. Result deficient

The first surprise is that the included instructions are only in English. For me, not a problem, but that is certainly not in any of the case.
The adjustment was made without any problems in the rail blank is held briefly in boiling water and is adjusted in the mouth after a short cooling time. Since the track is still hot you should not be too sensitive to heat.
Despite conscious advancement of the lower jaw in adapting my fiancee could not tell the difference in volume. This could possibly also be because you so easily in the relaxed state opens her mouth and thus lose contact with the rail.
I'm going to try yet more adjustment to make and change my review, I should find an adaptation acting.