Your Dish is an Eliptical with a dual-stacked LNB.
If you see the recordings in the DVR list and they have some non zero value, then they should play.
Obviously you have valid TV connections, else you wouldn't get the graphics up.
Are you using any HD outputs, DVI or Component?
What is the setting of the RED BUTTON, behind the fron panel on the right?
IF your mode was set for something that your TV couldn't display, like 720p on some older 1080i only sets, then it might be black but that doesn't explain your ability to watch it live.
Try turning the LOD buffer off and see what happens.
Also try swapping around tuner 1 & 2 cables from the LNB and see it that makes a difference.
The signals strength WILL be different as they show the values for whatever channel they are tuned to and in most cases, each tuner is on a different transponder, unless you are wathcing and recording the same program at the same time. If they values are wildly different THEN, you may have a tuner, LNB or Switch problem.
The eagle aspen is considered quite good., SO I suspect the LNB or Cabling.
Also call and have them do a factory reset with a hard disk format and have them stay on the line while you impulse record a few minutes of programming.
Once you see a minute or 2 in the list. Stop the recording. Change to a different channel and try and play the recording.
Also turn on LOD and try and PAUSE some show after a minute or so, If none of that works, insist that they replace the unit, it is defective and I'm not convinced that is a software problem, at least any I've come across since the beginning.