This is hardly a DIY project but I pass it on for what its worth.
Been having trouble with random flash over exposure for some while. The strobe was working fine on the manual strobe knob but occasionally behaving randomly using the housing manual mode or TTL. I bought a new sync cable to no effect.
Finally tracked it down to the hot shoe connector internals. The connector pins are spring loaded against a PCB and the spring on the quench pin had a rusty end. A quick burnish on 600 wet & dry together with the merest smear of copper grease got it working fine and reliably.
Be careful taking the connector apart, its just two screws but after that all the small springs and pins are free to fall out
Its not a sealed unit and clearly I've at some time disconnected it with wet hands - there's a moral there somewhere.
Having burnished the plating off the springs I don't consider this a permanent fix. Lets see if Ike can come up with some new springs!
