I would like to add my experiences. I have multiple receivers in the house, and a dish 722k that has been running great for years. Suddenly, it started rebooting a lot. Finally it seemed like it was happening more and more often or it ws bothering me more. So I called dish and exchanged the receiver - early December.
Here is where it gets interesting, the replacement receiver started rebooting within a day of being installed. So I started thinking it was something with my install. I unplugged my second tv (composite connections) and it instantly seemed a lot better. It was good for a few days, and then the rebooting came back. So I called Dish for help, but the csr didn't want to hear my story and she simply sent me a new receiver.
This time, I unplugged everything - ethernet / phone, and hooked up only coax in and hdmi out. That was about two weeks ago, and today my third receiver is locked up. Reset on the switch did not clear it, needed to be unplugged and plugged back in.
I have no idea why a system that has worked perfectly for years is suddenly eating receivers. No issues whatsoever with the other receivers in the house. Receiver is plugged in to a surge suppressor. I'm happy with the 722 and it works perfectly for what I need.