I'm fed up with the stupid string - well more specifically with the knot - in the top of my helmet digging in to my head. Aside from not wearing the helmet - which isn't very practical where I am... What methods can be recommended to pad out the top? I'm aware of the FFD in the top, but with the amount of sweat I'm likely to put into it I don't really fancy it getting up and walking away by itself one day... Also aware of the ammo box foam packaging - however this is pretty hard stuff and quite uncomfortable for prolonged wear. I'm aware of the new Mk6a helmet which is currently in production, but am unlikely to see it during this tour. The mesh inner is ideal - any ideas of anything similar? Ta.