Just paid for the upgrade, having moved over to Catalina. Playback is very jerky and out of sync, if the video pans across a scene you can watch it go in steps. No point in quibbling about missing features if the main purpose of the thing is so broken. Thinking of upgrading? I recommend you do not, this is not a patch on EyeTV 3.
I've got a brand new 2018 Mac Mini, with Mojave of course, and the Eye TV app works fine but there's no signal from the DTT tuner stick. Swapping it into the old Mini and it's fine, so nothing to do with the stick/aerial. Anyone seen this and got ideas??