Hello all, recently bought one of these from Amazon, paid around £40 for it. Straight out of the box i thought I'd test it with a bright LED torch. It darkens for a coiple of seconds and then goes back to its undarkened state. We i move the torch away it darkens again for a couple of seconds and then reverts to its undatkened state. First one of these helmets ive had so not sure what's wrong with it. Any help/thoughts would be appreciated.