I have a networked HDHomeRun Connect which displays live TV channels using the HDHomeRun app. But not as Live TV when using Plex Web or Plex Client eventually stopping with a “Playback Error – Could not tune channel” error. However TV shows are successfully recorded by the DVR function and will then playback using Plex.
Deleting and re-installing the DVR (HDHomeRun) made no difference. Either does Transcoding on or off. The server is 1.18.4.2171 on Ubuntu. Plex Web and Client from macOS.