Must've been the sound of the Yakima rattler strap stripping out for about
the hundredth time while tightening against my 120psi tires.
Or maybe it was trying to release the same strap, pusing repeatedly while
tugging up on the strap itself as it refused to come loose.
Bad design IMHO, the old cam/flip strap was far superior. Seems Thule
caught on;-]