As a first time poster, I'm having the same problem martin63. It's the reason I joined this forum in hopes of finding a solution.
I originally thought the problem was associated with the fact that I just added a Logitech Harmony 880 Universal Remote into my TV watching equation.
Based on what you are experiencing I am now fairly confident that there is no issue with the new Harmony 880.
Unfortuntely, this is doing nothing to alleviate the issue at hand. I am currently experiencing lockups every 20 minutes or so. The only thing that fixes it is to hit the reset button...wait a couple minutes...then pull the card and finally reseat the card.
...if it wasn't for the monopoly on the NFL Ticket I would have pulled the plug on Satellite TV Eons ago...I've been dealing with this pisspoor company for close to 20 years (back when they were called Pegasus Satellite)...
I hope someone can make a recommendation on how to address this issue for good...