I went to the range this weekend with my son and actually captured an odd function failure on video. My son was shooting my suppressed Glock 21. I was recording to see if I could find a sense on ho quiet it is.
Then the failure happened. Well, kind of.
It functioned normally except on the last shot the slide didn't lock back. It ejected the casing normally, it reset the hammer but it did not lock back.
--It's also pretty damn quiet.