Some clips showing up audio only inside FCP X

Hi there. Trying to see if others have noticed this as well. I have a project that I'm redoing in FCP X to get a better feel for it. It's a short, simple project, but has many elements to it in both HD and SD. I media managed it out of FCP 7 and then imported all the files into X.

In general, everything came in fine. However, a couple of clips originally digitized as DV/NTSC show up as audio only clips in X when clearly they have video attached. Has anyone else seen this happen?

Andy