"Keep Until I Delete"

I want to set my DVR to record episodes (I don't care if they are re-runs or new episodes) of Seinfeld, Friends, Mythbusters, and about 10 other shows.  Each of these shows come on about 5 times each day - and my DVR is, therefore, recording NONSTOP!  And multiple times each day I'll be watching TV and a warning box will pop up and say "must change channel or cancel one or both of the following recordings")

Here is my question: Why does my DVR keep trying to record episodes when it already has a recorded episode ready for me to watch?  For example, right now I have a Seinfeld recorded - but my DVR keeps recording EVERY Seinfeld (and every other show I watch) that comes on throughout the day and replacing the priorly recorded episode!  What part of "keep until I delete" does my DVR not understand?   It is driving me crazy.  

I set the series recordings to "keep until I delete" - but the DVR doesn't keep it until I delete it.  The DVR keeps deleting episodes only to replace it with another.  90% of these series are for shows that are only re-runs. Why does my DVR keep deleting one rerun only to replace it with another.   Why are the re-runs of Seinfeld and Mythbusters that came on at 2:00 so important that it should replace the re-runs that came on at 1:00?    

The real pain of this problem is that my DVR is CONSTANTLY recording - which makes it hard for me to watch LIVE tv (because my dvr is recording, for example, a Seinfeld and Mythbusters simultaneously for about 14 hours out of every day and, therefore, I have to repeatedly cancel recordings throughout the day so that I can't watch live tv.)

I will say that my TIVO doesn't do this.  When I told my Tivo to "keep until I delete" it actually kept each episode until I deleted it!  Brilliant!  If I already have a Seinfeld re-run recorded and ready for me to watch, why does my DirecTV DVR insist on recording another seinfeld and bogging down my live tv watching experience?  This is ridiculous!!!!! 

 I hate my brand new DirecTV DVR for this and it makes my whole TV watching experience pretty miserable.    For this issue alone I'd recommend people stay away from DirecTV, go with Comcast cable and get a Tivo.