I've heard a hissing sound coming from the right heel of my Trigon Guide several times over the last few days. Theres a tiny indentation in the foam on the inside of the clear plastic part of my shoe, which I'm guessing came from a thorn or nail. Are Saucony shoes like Nike Airs where the air itself provides cushioning, or does that all come from the plastic Grid itself? I don't mind the sound if the shoe is still fine, but if it isn't does Saucony have any sort of return or exchange program I could use?