I know this may seem obvious, However make sure that the Down coversion to DV output is not activated in the menu. As if your capturing in HDV and your down conversion is set to on. It will not see the camera as it's expecting an HD signal and when set to on it will send a DV source. This has happened to met several times. So if your capturing in HDV make sure your camera is set to down covert OFF, if capturing in DV turn the Down convert on.
Hope this helps!
J.D.