In this case, you have to look at the grounding system section, where the installer ground the system, and how, where the ground wire going ?
I did few services the last week with this matter. One just installed less then a week.
System never ground, although there grounding connection are close by, this installation just by-pass it.
Installer grounded the system through a cold water faucet, it could be the copper pipe just in this house but not all the way go to the outside main pipe.
Corrosion ground wire at ground block.
When all these happened, your system may encountered, freeze picture, loss channel, picture slow flashing, all this because the static electric build up on dish and no where to go, this all cause from the changed of weather, but, if the grounding is done correctly, it will go a long way without problem.
The first and second cases, I unplug the receiver(s), disconnected the coax on both side, ground block and at the receiver back, wait few second, then reconnect all, do the system test and download again, all back to normal. The third case, simple disconnected the ground block cable, clean the ground wire or replace with a new ground wire, go back to check switch and download, problem solved and this should good for sometime.