I am having the same thing happen to me. So I called Directv they are aware there is a problem and are working to fix it. That has been about 3 and Half weeks now so who knows.
Does anyone know if Directv receives a direct feed of the HD broadcasts? The reason why I ask is a Comcast tech told me that certain Pittsburgh affiliates have a direct connection to their head end instead of picking up an OTA signal. I live right near WPXI's tower and even though I receive a perfect 100 signal it still breaks up and drops to a 60 or 65 rating. This is not noticeable on Comcast.