i agree it depends there are some LNB's on whats called a cold weather recall after a nice storm of snow or really cold weather that LNB starts to fail during the day but not at night wierd i knw
i would check the alingment your transponders should be mostly 95's or higher on some its kind of hard trying to peak a swim without a meter. but check your 103c and your 99c and post the transponders if in the low 80's you need your dish repeaked.