I tried watching live TV (Baseball on Fox) for the first time in a while. All I got was a solid picture, like playback was paused. I tried a few other stations and they were the same. Then I started recording Fox and watched the file for a few minutes. Eventually it started stuttering but I stopped and started again and it was OK.
I walked into the other room and tried watching the same feed on my HDHomerun and it was working fine. I did notice that the game was out of sync on the two devices, with the HDHomerun 10-15 seconds ahead. I went back and stopped recording the game with JRiver and tried to watch it live instead. The broadcast started playing normally but it was still a few seconds behind the HDHomerun. I changed to another channel and the two systems were much closer to being in sync.
The game is over now so I won't worry about it too much. As you can probably guess, I rarely watch live TV and the recordings are still just fine.