Has anyone had any experience with this? Put the pairing through the paces in my first full season as a second wedding shooter last year so I was able to get a lot of use in. Sometimes the flash would go off but it's not even really doing anything for the exposure. Sometimes it doesn't even fire. Does this mean the TTL isn't communicating properly? I've seen some info online about people with the D700 having issues, but not the D3s. The shoe seems fairly tight. I mean the thing doesn't rock around like crazy in there. I have 2 SB900s and I'm pretty sure I've experienced this with both.
I know you said D3s but I have a D700 and had this same problem. I sent it to Nikon to be repaired and sure enough, it's the hotshoe is loose. If you put your flash in there and there is *any* play at all, it's a loose hotshoe. I hope you get your problem fixed and sorry to hear about it.
It is ridiculous, IMO, that using a Nikon camera and flash together, would result in a problem like this. I had to pay for this repair too.