H20 Amphibix is the way to go! been using it for 4years now not a prob, just wash the sand out of seal if you dump it in sand when taking off your rashie. fresh water rinse out headphones so they dont get too corroded over time.
you might spend a bit but its definatly worth it, expecially if you get stranded either kiting or SUPin or you need to ring some one quicksmart.
Kite power stock them and the 3s headphones (headphones for hands free).
Get the older H20 Amphibix armband style and not the newer H20 armband style as its not as secure and you cant fit your electronic Key inside too.
Good winds and happy tunes!!