Upload & Sell: Off
Sorry to revive an old thread, but I am having this same problem. I got my D600 on Thursday and had a event gig on Friday night where I needed to fire my remote flashes with the commander mode (sb900 and sb600). It worked for the first 15 or so shots and then wouldn't trigger the flashes anymore. Luckily I had my D700 (always have a backup) and it faithfully controlled the flashes perfectly just like it has for the last 4 years.
With more testing, I realize that there must be something wrong with the pop up flash. When using it in TTL mode, it overexposes probably 3-4 stops but sometimes will expose correctly. Also, when it is in commander mode, with the built in flash set to TTL, it will not fire. Actually it fires a pre-flash, but nothing that actually adds to the exposure.
This is so strange, I have been using CLS in my professional work for years and never had problems like this. I am sending the D600 back to Amazon.