In-laws (south side of DSM, not far from the airport) are still having problems with 5.1. A couple weeks ago, I put a new antenna (link) on their roof and pointed it north. When we checked, 5.1 came in perfectly. I e-mailed him today, asking how the antenna was working. Said he's only able to get 5.1 part of the time. He said when they do get it, much of the time it's unwatchable as the signal is skipping and pixelated. Any suggestions?