There is something wrong with that hood and it should be replaced and if the next one does the same thing raise a stink until you get your money back, they will give you a refund if you complain after the second one. Don't worry about the flash you have been getting since those things WILL provide UV protection even if they don't go dark. It is very un-nerving and uncomfortable when they fail to darken but you will not burn your eyes. I know you will hear all these "urban legend" sob stories about welders going blind from these things but that is pure BS since there is a government mandated safety standard that requires 100% UV protection even in the lightened stage, that is why you can't get one that goes completely light. The same cannot be said for your damaged Jackson, TOSS THAT THING! It may very well allow undetected UV rays even in the dark stage because of the damaged lens and UNDER NO CIRCUMSTANCES should you continue to use it!