That’s not surprising as live tv streaming is much more sensitive to latency and network disruptions. You can check the System Log on your hdhomerun to see what it says.
Just curious, isn’t the DVR capturing live TV stream just like the Apple TV? Why would the Apple TV be more prone to Network Latency issues compared to the DVR getting that same Live Signal. Why are the recordings always in perfect condition, but viewing live tv might cause connection error? Just trying to get a clearer picture of what could be causing this for some users. It makes sense that it is network issue causing the problem. But I have never heard of DVR recordings being messed up, only LIVE TV. Just wondering.
If the DVR can make recordings with issues, that means the connection between the DVR and the HDHR is fine, but the connection between the ATV and the HDHR is not.
Some users have been reporting problems with Apple TV wifi since tvOS 11.3, but in this particular case the problem is happening over Ethernet as well, and also happening on iOS and with the HDHR app as well.