surely there is some simple solution. after all, when i left the
dealership
with the boat on top, i drove about 75mph for an hour to my destination
without a sound--and the damn straps were absolutely flat.

help! or do i just pop for those thule thingies...?

It IS the straps vibrating. I've been thu all this before as well, even to
the extent of no noise on the first trip home with the boat !!

Keep twirling the straps on every length exposed to the wind. This includes
the lengths at the side and especially underneath the roof-rack. You'll get
there in the end. It took us some trial end error but we travel in peace and
quite now, well, except for the kids fighting in the back !

J