I have a couple of Profoto Compact 600 monolights.
Earlier today when I put the power on one of them it just started flashing rapidly from the moment I turned it on and till I turned it off. Sync cable is not plugged in or anything and it wasn't placed in a highly lit area. The other strobe didn't do this at all. I have tried putting the sync cable in it, no difference.
Does anyone have an idea what could be wrong with it? I haven't used it for quite a while as I mostly just use one of them.