Hydrophone placed about 6 inches below the sand at the shore line. The rustling is the sand moving across the microphone and you can also hear the rumble of the wind above ground.
I buried a hydrophone about 6 inches into a sand dune below some of the grass. The result, on a very windy day in North Norfolk, was this amazing sound. It sounds more like bamboo rattling together with the occasional whoosh of wind as it raced across the sand above.