[mythtv-users] Programs start recording late: why, and how fix?

[Brad Allen]

I'm having a lot of programs start recording late.  I've been running
NTP since 1980s, so that's not the problem.  When I view the program,
it obviously skipped important scenes at the beginning.  The only
program I know of which has important scenes at the end is South Park,
but almost everything I watch besides South Park has important scenes
at the very beginning of the hour, including Everwood and Stargate
SG-1.

My settings for prerecord and postrecord are:
  mythfrontend:  Setup:  TV Settings:  General:
   Time to record before start of show (in seconds):  10
   Time to record past end of show (in seconds):  20

Here's Everwood in mythbackend's log:  <<<<<<<<<< are my comments:

2004-01-25 17:59:51 Started recording "Everwood" on channel: 2015 on cardid: 3, sourceid 2
2004-01-25 17:59:51 Changing from None to RecordingOnly <<<<<<<<<< s/b OK?
2004-01-25 17:59:51 Using profile 'Default' to record
2004-01-25 18:00:02 Changing from RecordingOnly to None <<<<<<<<<< what?
--- print list start ---
Title                 Chan  ChID  StartTime       S I C  C R O N Priority Total
Star Trek: Enterprise   35  1035  Jan 25 06:00pm  1 1 1  0 1 0 1        0   10
The Simpsons            12  2013  Jan 25 07:30pm  2 3 3  0 1 0 3        0    0
The Simpsons            35  1035  Jan 25 08:00pm  1 1 1  0 1 0 1        1   11
[...]
---  print list end  ---
2004-01-25 18:00:05 Found changes in the todo list.
2004-01-25 18:00:05 backend still changing state, waiting..
2004-01-25 19:00:02 Changing from RecordingOnly to None <<<<<<<<< but it already did this.
2004-01-25 19:00:04 Estimated bitrate = 384000
Input #0, mpeg, from '/v/rec/2015_20040125180000_20040125190000.nuv':
  Stream #0.0: Video: mpeg2video, 720x480, 29.97 fps
  Stream #0.1: Audio: mp2, 48000 Hz, stereo, 384 kb/s
2004-01-25 19:00:04 Position map found


Input was a '350.



Do you think channel 14 (chanid 2015; Comcast "WB" channel in Santa
Cruz County) actually started early?  Should I just get a whole bunch
more '250s so I can set prerecord to a minute?  If so, what settings
work (i.e., 30, 45, 60, 80, 100, 120 seconds, etc.)?