When flying near ground level or jumping over torches they make a wooden sound. Also applies to redstone torches, levers, pressure plates and snow layers, as well as when jumping over 0.5 sized blocks like slabs and stairs. This seems like a bug as they make sounds while the player is in the air above them, unlike with regular blocks where you need to be pretty much in contact with them and in the case of non solid blocks like torches it feels like they shouldnt make sounds at all.