Have you tried using the basic satellite setup?
Go into the Menu, Setup, Tuner and Scanning, and set the configuration mode, to simple, single LNB, for 0.8W, and then check if you can scan in any channels.
The reason I wanted you to test your Duo 4K, on one of the other LNB's, currently connected to your Duo 2, was to confirm that the problem wasn't with your receiver, as you can alter your LNB settings, on your receiver.
The basic reasons, for loss of signal, are:
1. Cable problems, either a break, in the cable, or the F Plugs not done correctly. I had a problem, when I set up my system, as the F Plug was too tight, for the cable, and cut off nearly all the braid, causing an intermittent problem.
2. The dish has moved, and no loger aligned.
3. The LNB has failed.
4. The receiver has a fault
5. The Tuner configuration is wrong.

Go into the Menu, Setup, Tuner and Scanning, and set the configuration mode, to simple, single LNB, for 0.8W, and then check if you can scan in any channels.
The reason I wanted you to test your Duo 4K, on one of the other LNB's, currently connected to your Duo 2, was to confirm that the problem wasn't with your receiver, as you can alter your LNB settings, on your receiver.
The basic reasons, for loss of signal, are:
1. Cable problems, either a break, in the cable, or the F Plugs not done correctly. I had a problem, when I set up my system, as the F Plug was too tight, for the cable, and cut off nearly all the braid, causing an intermittent problem.
2. The dish has moved, and no loger aligned.
3. The LNB has failed.
4. The receiver has a fault
5. The Tuner configuration is wrong.
