Pixels on clips after importing to FCP from Canon XA10

I have been using FCP for years with my Canon XA10 video camera without problems. I have however now faced a very strange issue. After importing clips from camera to FCP, some of the clips have some pixels/interference on picture which last for a second or so.

I thought my camera was broken and sent it to Canon. They reported that the camera has no problems. They believe it is due to different codec. The camera uses AVCHD whereas Apple uses different and its own codec which it needs to transcode.

I have also tested this myself and this error occurs also in iMovie and with a different Apple computer. So this issue is not computer specific or only FCP specific. And as said, I have used FCP and same camera for years with iMac without any problems.

Any suggestions? Thanks for any help/comments!