Recently purchased a used Metz 60 CT4 from KEH. Unit was not working (lightup but no flahses, not even one) so I sent it back. They gave me another one which seemed to work great (out of the box I got a bunch of fast recharge flashes). However, now the unit seems to be becoming inconsistent. Half of the time it simply wont fire, but Im not sure if the battery is just dieing or there is something wrong with the unit. I have the standard charger and a dryfit battery - the red charge light never seems to go out. Is my charger bad? Or is there something wrong with the pack?