[mythtv] DVB "Transport Continuity" errors locking mythfrontend, dropping audio in recordings, etc.

[Blammo]

I've been having trouble with two issues:

1. with Mythfrontend lockups while watching either recorded or live
HDTV (always ABC)

2. audio complete dropout, either midway through a program (HDTV,
always ABC) or while watching live TV. This doesn't happen on my
PVR-250 at all, just the Air2PC.

This doesn't happen on any other channel. I'm using an Air2PC card on
the back, MythCVS from Sunday.

I finally started digging though the logs a little bit after it either
locked up the mythfrontend process, or stopped recording audio on the
backend process (3) times during the NYPD blue series finale  (which I
was watching just in CASE this happened).

In all cases, either stopping and starting the recording, or leaving
and coming back to live TV restored the audio. In no case did it lock
the backend, just the front. There were NO detectable video artifacts,
breaks, etc, to make me think it might be signal quality related.
There were no commflag jobs running on the backend at the times I
experienced problems.  At least once tonight I was able to EXIT back
to the menu, then go back to LiveTV.

One lockup, while watching LiveTV, was at 21:46:55, so I'm going to
post the logs from then. The audio dropped out after a commercial
break, and didn't come back. Exiting to menu, and back to LiveTV
restored the audio.

 I'm going to post back to 21:30 when we started, so you can see the
signal strength, that it didn't lose signal, etc. From what I can tell
fda0 is a strong signal:



2005-03-01 21:30:51.456 DVB#0 DVB Signal Monitor Stopped
2005-03-01 21:30:55.432 DVB#0 DVB SI Table Parser Started
2005-03-01 21:30:55.433 DVB#0 Using DVB card 0, with frontend Nextwave
nxt2002 VSB/QAM frontend.
2005-03-01 21:30:55.435 DVB#0 DVB Signal Monitor Starting
2005-03-01 21:30:55.438 DVB#0 Signal Locked
2005-03-01 21:30:55.878 DVB#0 Signal Lost
2005-03-01 21:30:56.135 DVB#0 Signal Locked
2005-03-01 21:30:56.437 DVB#0 DVB signal fda0 | snr e47e | ber    0 | unc    0
2005-03-01 21:30:56.442 DVB#0 Status: LOCK.
2005-03-01 21:30:56.444 DVB#0 Multiplex Locked
2005-03-01 21:30:57.563 DVB#0 Successfully tuned to channel 15_1.
2005-03-01 21:30:57.569 DVB#0 Recorder: Card opened successfully
(using PS mode).
2005-03-01 21:30:57.575 DVB#0 AutoPID selecting PID 49, MPEG-2 Video
2005-03-01 21:30:57.577 DVB#0 AutoPID selecting PID 52, AC3 Audio
2005-03-01 21:30:57.578 DVB#0 AutoPID Complete - PAT/PMT Loaded for service
2005-03-01 21:30:57.583 DVB#0 Service is FTA
2005-03-01 21:30:57.585 DVB#0 Adding pid 49
2005-03-01 21:30:57.586 DVB#0 Adding pid 52
2005-03-01 21:30:57.591 DVB#0 Data read from DMX - This is for
debugging with transform.c
2005-03-01 21:39:08.769 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:39:08.801 DVB#0 PID 52 _continuity_count 4 cc 9
2005-03-01 21:41:09.300 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:41:09.338 DVB#0 PID 52 _continuity_count 1 cc 7
2005-03-01 21:41:09.387 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:41:09.390 DVB#0 PID 52 _continuity_count 15 cc 1
2005-03-01 21:46:36.433 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:36.474 DVB#0 PID 52 _continuity_count 6 cc 12
2005-03-01 21:46:36.517 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:36.519 DVB#0 PID 52 _continuity_count 4 cc 1
2005-03-01 21:46:36.522 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:36.523 DVB#0 PID 52 _continuity_count 9 cc 1
2005-03-01 21:46:52.909 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:52.914 DVB#0 PID 52 _continuity_count 3 cc 1
2005-03-01 21:46:55.799 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:55.805 DVB#0 PID 52 _continuity_count 4 cc 10
2005-03-01 21:46:55.884 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:46:55.885 DVB#0 PID 52 _continuity_count 3 cc 1

At this point the audio is gone, so I flipped out to the menu, and back in again

2005-03-01 21:47:06.594 Closing DVB recorder
2005-03-01 21:47:06.596 Closing DVB channel
2005-03-01 21:47:06.752 DVB#0 DVB Signal Monitor Stopped
2005-03-01 21:47:08.822 DVB#0 DVB SI Table Parser Started
2005-03-01 21:47:08.824 DVB#0 Using DVB card 0, with frontend Nextwave
nxt2002 VSB/QAM frontend.
2005-03-01 21:47:08.825 DVB#0 DVB Signal Monitor Starting
2005-03-01 21:47:09.398 DVB#0 Signal Locked
2005-03-01 21:47:09.829 DVB#0 DVB signal fe10 | snr e44e | ber    0 | unc    0
2005-03-01 21:47:09.834 DVB#0 Status: LOCK.
2005-03-01 21:47:09.836 DVB#0 Multiplex Locked
2005-03-01 21:47:11.018 DVB#0 Successfully tuned to channel 15_1.
2005-03-01 21:47:11.023 DVB#0 Recorder: Card opened successfully
(using PS mode).
2005-03-01 21:47:11.026 DVB#0 AutoPID selecting PID 49, MPEG-2 Video
2005-03-01 21:47:11.028 DVB#0 AutoPID selecting PID 52, AC3 Audio
2005-03-01 21:47:11.029 DVB#0 AutoPID Complete - PAT/PMT Loaded for service
2005-03-01 21:47:11.029 DVB#0 Service is FTA
2005-03-01 21:47:11.031 DVB#0 Adding pid 49
2005-03-01 21:47:11.033 DVB#0 Adding pid 52
2005-03-01 21:47:11.112 DVB#0 Data read from DMX - This is for
debugging with transform.c


It was fine until 21:59:05, when the station flipped aspect (I hate
seeing them do that before the end of the show) at which time we lost
audio again:


2005-03-01 21:59:05.039 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:59:05.070 DVB#0 PID 52 _continuity_count 7 cc 13
2005-03-01 21:59:05.124 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:59:05.125 DVB#0 PID 52 _continuity_count 6 cc 1
2005-03-01 21:59:07.920 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:59:07.926 DVB#0 PID 52 _continuity_count 10 cc 0
2005-03-01 21:59:08.004 DVB#0 WARNING - Transport Stream Continuity
Error. PID = 52
2005-03-01 21:59:08.009 DVB#0 PID 52 _continuity_count 9 cc 1
2005-03-01 22:00:19.900 Closing DVB recorder


Here's what the frontend showed for the times time period:

2005-03-01 21:46:54.875 positionMap[ 57595 ] == 1295597269.
2005-03-01 21:46:55.124 positionMap[ 57610 ] == 1295938568.
2005-03-01 21:46:55.376 positionMap[ 57625 ] == 1296274299.

[many many lines of waiting for prebuffer, wait timed out]

2005-03-01 21:47:06.283 waiting for prebuffer...
2005-03-01 21:47:06.351 prebuffer wait timed out..
2005-03-01 21:47:06.351 waiting for prebuffer...
2005-03-01 21:47:06.419 prebuffer wait timed out..
2005-03-01 21:47:06.419 waiting for prebuffer...
2005-03-01 21:47:06.487 prebuffer wait timed out..
2005-03-01 21:47:06.974 Changing from WatchingLiveTV to None
2005-03-01 21:47:06.980 Changing from None to None
2005-03-01 21:47:08.538 Using protocol version 14


Then started back up again, with audio:

2005-03-01 21:47:11.815 AVFD
2005-03-01 21:47:11.816 AVFD: Opening Stream #0: codec id 2
2005-03-01 21:47:11.817 detectInterlace(Detect Scan, Detect Scan,
59.9401, 720) ->Progressive Scan
2005-03-01 21:47:11.817 Interlaced: Progressive Scan  video_height:
720  fps: 59.9401
2005-03-01 21:47:11.817 AVFD: Looking for decoder for 3
2005-03-01 21:47:11.817 AVFD
2005-03-01 21:47:11.817 AVFD: Opening Stream #1: codec id 86020
2005-03-01 21:47:11.817 AVFD: Looking for decoder for 86020
2005-03-01 21:47:12.070 Estimated bitrate = 45384
2005-03-01 21:47:12.077 Filling position map from 0 to 64
2005-03-01 21:47:12.086 Position map filled from Encoder to: 53
2005-03-01 21:47:12.086 SyncPositionMap liveTV, from Encoder: 4 entries
2005-03-01 21:47:12.086 Partial position map found
2005-03-01 21:47:12.089 Opening audio device '/dev/dsp'.
2005-03-01 21:47:12.089 Opening OSS audio device '/dev/dsp'.
2005-03-01 21:47:12.102 Over/underscan. V: 0, H: 0, XOff: 0, YOff: 0
2005-03-01 21:47:12.109 XvMCSurfaceTypes::find(w 1280, h 1, c 0, i 2,
m 0,sw 0, sh 145, disp, p<= 145, 7200 <=p, port, surfNum)
2005-03-01 21:47:12.109 Trying XvMC port 145
2005-03-01 21:47:12.109 XvMCSurfaceTypes::find(w 1280, h 1, c 1, i 2,
m 0,sw 0, sh 145, disp, p<= 145, 7200 <=p, port, surfNum)
2005-03-01 21:47:12.109 Trying XvMC port 145
2005-03-01 21:47:12.109 Found a suitable XvMC surface 0
2005-03-01 21:47:12.110 Using XV port 145
2005-03-01 21:47:12.136 Image size. dispxoff 0, dispyoff: 0, dispwoff:
888, disphoff: 508
2005-03-01 21:47:12.137 Image size. imgx 0, imgy: 0, imgw: 1280, imgh: 720
2005-03-01 21:47:12.999 Realtime priority would require SUID as root.
2005-03-01 21:47:13.043 Changing from None to WatchingLiveTV
2005-03-01 21:47:13.126 nVidiaVideoSync: VBlank ioctl did not work,
unimplemented in this driver?
2005-03-01 21:47:13.126 DRMVideoSync: Could not open device
/dev/dri/card0, No such file or directory
2005-03-01 21:47:13.126 Using audio as timebase
2005-03-01 21:47:13.126 Video timing method: RTC
2005-03-01 21:47:13.126 Refresh rate: 16663, frame interval: 16683


I can't find anything in the logs to indicate the frontend realized
the audio was gone. Not sure if I have the right debugs up.

The fact that HDTV ABC programs have about a 90% chance to lose audio
somewhere in the program, and not get it back, has my WaF (wife
acceptance factor)  very low at the moment with HDTV sources.

I'll try to pull some backtraces the next time this happens. Any ideas
in the mean time?