I have two of these and one of them has started playing up. The light turns from red to green pretty quick but then just starts going red/green/red/green again and again, after a short time of doing that it will fire about 3 times and no light will show for about 2 mins before it repeats the whole process again.

Whereas the one that is working fine will go to green very quickly and stay on that for a few shots and never misfire.

Help please?