I have exactly the same issue with poor quality on signal one and sometimes none on input 2. I self installed sky hd and my alignment is fine as i plugged my old single lnb in and rechecked the strength/quality. Therefore i deduced it is the lnb and have ordered a new dual one as ive heard quad arent as good anyway.
1. Press services on your Sky remote control.
2. Highlight System Setup using the up/down arrows and press select.
3. Press 0, then 1, then select.
4. Press select again to access the LNB setup screen.
5. Using the up/down arrows, highlight LNB Power Supply.
6. Using the left/right arrows change the setting to off.
7. Using the up/down arrows, highlight 22KHz command.
8. Using left/right arrows change to off.
9. Using the up/down arrows, highlight Save New Settings and press select.
10. Press sky followed by services.
11. Highlight System Setup and press select.
12. Press 0 then 1 then select.
13. Press select again to access the LNB setup screen.
14. Press the red button to re-set the default settings.
15. Using the up/down arrows, highlight Save New Settings and press select.
16. Press select to confirm that the settings have been reset.
The correct settings are:
- 9.75 for the low frequency.
- 10.60 for the high frequency.
- The LNB power supply should always be set to on.
- The 22KHz Command should always be set to on.
17. Press sky to return to normal viewing. It may take 60 seconds for the picture to appear. If this issue is affecting the playback of recorded material, you will need to make a new recording to check whether this procedure has resolved the issue.
I'm adding to this thread because I feel it's misleading.
An LNB itself can not be "reset". It's not a computer and there's nothing inside it that can be "reset". However, what you CAN do is put the LNB settings back to factory defaults and that needs only a couple of button presses in the LNB menu.