Currently Being ModeratedMay 3, 2011 9:14 AM (in response to Michael Guncheon)
So it turns out that the first clip that I tried with the Sony F3 happened to be timelapse clip. (The camera has that feature, this particular clip was 1 frame captured every 5 seconds.)
I tried other clips shot 'normally' and they came okay.
For this timelapse clip I tried running it through compressor first (changing frame rates etc) to no avail.
The one thing that worked was to place it in a sequence (letting FCP choose the sequence settings) and then exporting the sequence (self-contained, with sequence settings as is).