I've got an external eSATA drive on my (owned, thanks to Rich) HR20-700. In the last month playback has become more and more flawed with Skips, Stutters and freezes. This despite weather or channel. Thus I conclude she needs re-formatted or whatever it takes. Problem is I have never had to do this and don't' know the process. Meanwhile we watch and record to the other box. And DTV knows of both btw. So what are the steps to take please ?