Why don't we make a bracha on the sense of hearing, like we make on seeing פוקח עורים ?
?וְכָל בְּרָכָה מֵהֶן שֶׁלֹּא נִתְחַיֵּב בָּהּ אֵינוֹ מְבָרֵךְ אוֹתָהּ: - כֵּיצַד
לָן בִּכְסוּתוֹ אֵינוֹ מְבָרֵךְ כְּשֶׁעוֹמֵד מַלְבִּישׁ עֲרוּמִים."
Any of the above blessings for which there is no occasion, [the obligation is not renewed - נתחייב, my translation] is not recited. For example: If one passed the night without removing his clothes, on arising in the morning he does not recite the blessing, "Who clothes the naked".
Therefore, if we assume that we hear all the time even when asleep, we don't feel the moment of enjoying this sense and therefore we don't say a blessing.
However, since we use to recite all blessings together at a shul, regardlessly of previous experiences, (as we Pasken that a blind person does say the Brocho on seeing), it seems that the reason is invalidated. But as we can't add Brochos of our own, we're, IMHO, stuck without this Brocho.