[mythtv-users] When and how does MythTV class a recording as failed?

[nospam312]

Does anyone know what conditions MythTV uses to decide to set an
upcoming programme as Failed.

I have an intermittent problem where recordings just say Tuning (Black
in the Terra theme) and eventually they fail (turn Red in the Terra
theme) and get rescheduled.

They seem to take a long time to fail and I am wondering what
conditions are used to set the recording to failed?

The programme may be reshown 1 hour later on a timeshift channel but
the entry is still in the Upcoming Recordings half way through the
original programme?

TIA