when my nano is plugged in to the mac and is on the charging screen there's a little red dot that appears near the top, and it also appears in other applications as well over a black border.
Try playing a pixel-fixing video on the iPod. They're meant for LCDs, so I don't know if it will work (but it certainly wouldn't hurt to try ).
I used to go to this one website with an actual downloadable file (which you could then place in iTunes and convert it, or however you would want to put it on your iPod), but I don't know where it went. This is more or less the same concept though; you could download the video from Youtube via deturl.com.