No HD signal?

We've been experiencing sporadic HD signal this past week. I noticed it around wednesday of last week when I was checking to see if I still had the Big Ten Network. Kept looking for a signal and would come on once in a while and fade out? My son was just watching it a bit ago and said where's the HD'ness'? :) Any ideas or just call Dish?

Teresa

change in the season maybe?? More trees etc so worse signal

I would call Dish, explain the situation and see if they will schedule a dish re-aiming...