The dominant factor is probably in a relaxed state and minimized activity. Because up to this point you were constantly doing something, then those same mysterious "strange clicks", most likely, were elementary not taken into account, since you had more important actions on your mind than tracking extraneous sounds. Secondly, they could simply not be heard, because even a not particularly noisy computer turned on can safely block some rustle, etc., but it is worth adding to it the rest of the background noise, which can be supplemented by your activity, and even cutting hearing creak goes unnoticed. Of course, there is no sacredness in this.
I suppose because you close your eyes and the brain can better process information from other senses, ears, for example. When you close your eyes and kissing becomes more pleasant, and sex, and food and alcohol.