Z1 HDV slow pan 'judder' in FCP
 

I know this issue has been partly addressed in other threads but wondered if anyone could clarify the current view on the following: I have shot HDV on a Z1 and the footage has been captured in HD with FCPro. Slow pans, and particularly on close ups, show a 'juddering' or strobing to the motion looking a bit like a field order problem. Footage down converted and edited in SD does not appear to show the problem. I have read that there may be a problem with FCP handling HDV, is this still considered the most likely cause of this effect? Any help would be appreciated.