Intermittent 'no signal' on certain channels.

[spireman123]

Over the past few weeks i have been getting intermittent 'no signal' message on certian channels yet other channels are fine. Weather hasn't been a problem and the signal is restored to these channels afetr a period of time. I don't think its the LNB. Any ideas?

[Mark39]

I assume that's  'no satellite signal'. 

What do your signal strengths look like? The white part of all 4 bars should extend at least half way across and remain fairly constant.

[spireman123]

None on Input 1 but on Input 2 strength 3 quarters, signal quality 90%.