Any theories on how the shackle is opening up? I use the Ronstan-style spring pull with a 2 inch tether. Maybe I should start taping the mechanism.

:: The last race we started having the spinnaker halyard
:: shackle open in 3 of the 5 races. I have since cut off
:: the shackle and we will now tie on the spinnaker
:: halyard, too.