My bet is the cable is using 1080i and some cable top boxes tend to show a little imperfection like that.

While it's far better than pre-HD days, I find today's folk to be more picky. Since no cable co is always on 1080p, you have choices to make.

As to the camera pan issue. When you see that, backup and examine the screen FRAME by FRAME. If each still frame looks OK then try turning off any video processing such as auto motion. If the frame is showing this, then it's burnt into the source and you won't be removing it.

Hope this helps,
Bob