Hi had partly the same problem: I.e: I shot with two identical Panasonic cameras. By error they had two differnt settings, one progressive scan, the otehr interlaced.
The interlaced caused me the same problem as mentioned above.
At https://forums.creativecow.net/thread/8/1123103 I found this solution from Noel Evans:
“Noel Evans
06-02-2008, 12:18 AM
Open QT
Under QT Player menu choose preferences
Window will pop up … last item on the list is Final Cut Color compatability – select it.
Done.”
Seems to hav esolved the problem for me.