Direct TV Local HD Question

[florad]

I FINALLY got 2 of my local channels in HDTV. One morning I wake up to watch the local news and POOF! HDTV. LOVED IT! (even if I only got 2 for now). So last week I was watching NBC and the sound kept coming in and out, so I reset the receiver. After that point, I got a download for the receiver and then all of a sudden my programming from the morning until the nightly news came with the black bars on the side. So I called Directv and they had no clue and sent out a young kid yesterday to take a look. He tries to tell me that having black bars on both sides of the tv is how my local market broadcasts my HDTV signal. I told him he was full of it and that when you get a standard definition signal on an HD channel, bars are what you get. He said he's worked on TONS of pictures and that I was wrong. Am I? It's strange though - from the start of the morning until 6pm you get the bars (Except for the Today show), and once national programming comes back on I'm back up in HDTV. 2 weeks ago it worked just fine. Anyone have any clue? Sorry for the long question.....