The camcorder is pretty much irrelevant because it is outputting analog, AV, signal to the Canopus box.
We don't know which Canopus box you are using. I presume ADVC55 or ADVC110.
If you are having the same problems with iMovie *and* FCP X, perhaps contacting Grass Valley (I believe they acquired Canopus a while back) is in order. I was poking around the https://discussions.apple.com area (searched using "canopus advc"). I did not find much related to FCP X, but there were some import setting prefs for other versions of FCP that looked like they had potential.
We assume the import preferences for FCP X are appropriate for standard definition, DV format, video importing. The rolling tells me there's a sync issue. If the camcorder playback heads were the problem, I would expect playback in the camcorder to be problematic - but you say that is OK...
Just for grins, I presume when the camcorder is connected to a TV (rather than the Canopus analog/digital converter), that the image is OK, too...