Don't know. But the problem wasn't with every glock although it did happen several times with my one glock and I am a gun guy who cleans and cares for his weapon. But since at the time the nypd contract was the biggest in the country it is not surprising that it appeared more often with them

But it is gone away now so a better question is what did glock change, and why did they let cops carry them knowing there was an issue? The sig and smith worked just fine all that time