Mine stayed green the whole time and I heard a faint buzzing noise if that makes sense. Eventually battery symbol went from around 20% to fully charged and it has worked fine. But as mentioned, I will not use it again because that adapter has been discontinued for quality issues. One more note about the adapter, the 6V setting produces 8.86V but I am not going to chance using a questionable product on my IPV3.
Can you try holding down your fire button for 10 seconds or so as you pop the batteries in? maybe it will show a different firmware revision?