Hi I have had recurrent problems with the picture freezing on live TV since before Christmas.
My setup is a HDHomeRun Quattro plugged into an Orbi Router.
I have a Apple TV plugged directly into the same router then connected to a Samsung TV via HDMI. This has the problem but was fine previously. If I use the built in tuner the picture is fine.
I have another Apple TV, the 4K version. This connects to the HDHomeRun wirelessly and connected to another Samsung TV. This works flawlessly.
Both Apple TVs have the Channels app.
I have the DVR software running on a Mac Mini and connected to the 2nd Orbi Router.
I’ve sent some diagnostic logs yesterday but not sure if this helps.