I've noticed this problem for a few weeks on WTEV CBS 47 and WAWS FOX 30 when watching football on Saturdays and Sundays. I'm watching the HD feed either OTA (from Julington Creek) or through Dish Networt. Every 10 minutes or so, the signal will cut out and then return within a few seconds. I usually watch OTA and was thinking it could be a multipath problem (I used to have this issue with the ViP 622 receiver in North Carolina) but it happens at the same times on the HD channels through Dish. If watching OTA, the receiver says the OTA signal has been lost whereas if watching over Dish, it says the satellite signal has been lost. When the signal cuts out OTA, I can actually switch to the Dish channel immediately and see it out there too.
As I understand it, Dish has a local antenna receiver which then feeds the local channels to a satellite. I'm assuming that receiver is located somewhere other than where I am and, hopefully, close and with a better signal. So I'm thinking the problem is with the broadcast.
My wife reports that her shows have dropouts on ABC and NBC, but she's only recording OTA. I'll try switching her shows to Dish channels and see if that matters.