Additionally, you can no longer uninstall the app to reinstall the old version that works anymore since its a system app now.
It blows my mind how Google still hasn't fixed this issue as HDHR TV tuners are one of the most popular TV tuners out there. Before, I would just load the August 2017 version and it would work again.
I fixed it by installing the HD Homerun app. The HD Homerun app then appears as a channel source in Live channels and you can add the channels. I disabled the native channels and everything works flawlessly. Hope this helps!