As for recordings just not recording with no error log and no indication it was even supposed to record. I gave up long ago on this issue. If the HD Homerun has the slightest “hiccup” during recording, then entire recording can just disappear. Also, the recording can fail to start and then it will try again in a few minutes and you will loose several minutes at the start. A work around for this is to start the recording 7 minutes early. Like I said, no one has ever fixed or even addressed my issue and I have had Plex for at least 4 years.
My “fix” was to also get Emby. I run two different servers one with Plex and one with Emby. I have 8 tuners. Sometime Emby fails but it is rare. Some time Plex fails (this happens once every 8 or 10), but between them both I only miss recordings during very bad weather.
Sorry I do not have a great answer or a real fix. I’m just letting you know what I did to make my life bit better.
