just got a yongnuo YN-622N TX trigger and also 2 un-622 receivers. First off I need some explanations on what/how the delay works? I've had some issues with Miss fires on ttl. The flash is on ttl, AF on, trigger on ttl and the zoom on AU which when I zoom in and out I can hear the flash motor adjust the zoom. I can get it all to fire but every once in a while it will throw a burst of light as a miss fire. Is there a setting I'm missing?? Any ideas?