Why is it called Ocean Waves?

The original title is "I can hear the ocean" (or the sea).
Surely some kind of metaphor, but does not seem very clear.

Some material in other thread
http://www.imdb.com/title/tt0108432/board/flat/27776513?p=1

and I copy some texts from a mailing list:

Remember that the movie is mostly set on an island, and my impression
of it is that when you grow up with something, you can't really hear
it... and new realizations and experiences can make you step back and
really hear anew what you have become so used to.

The self-centeredness of youth is a major motif of the film, after all, and
the scene where they actually stand and admire the sea (with the music)
is the first one after they graduate and "grow up", IIRC. Also, the
grammar seems to suggest this to me: "Umi ga kikoeru" is a phrase
typically uttered in mild surprise, an everyday epiphany, like "Hey,
that sound - it's the ocean!"

The title confuses a lot of people and I don’t think there is a
definitive answer, just like “If You Listen Closely”, different
readers/viewers take away different impressions of it. For me though
there are two key scenes. 1) where the two boys spend time on the end of
the dock at the end of the movie and Matsuno realises Morisaki is in
love with Rikako and that she is lost to him. That moment of
understanding is like him hearing the sea for the first time. 2) At the
end again when they leave the end of school party and stand below the
temple. To me I hear trees rustling in the wind there and that too is
sometimes like the sea. Morisaki here has his moment of realisation that
he loves Rikako, and she him, which is why the sounds here are
important.