Recordings fail with firewire changer, but liveTV is OK...

[lglenn]

Hello:

I am having a strange problem tuning channels on my Scientific Atlanta 3250 HD STB. I am running Mythbuntu 9.10 (MythTV MythTV 0.22.0~zrc1), and I am wondering if anyone else has encountered (and maybe fixed?) a similar problem.

I am using the sa3250ch external channel changer program over Firewire, and have the analog (“cable”) out from the sa3250 connected to a Hauppauge PVR 150 encoder card. When watching live TV, I am able to change the channel on this input with no problems. However, at least 80% of the time that the system attempts to record a program on this input, it fails. I either get an unwatcheable file, or one that is severely corrupted, and often causes the frontend to crash. There’s nothing in the backend log that indicates that the system is having a problem recording the program, it’s only when it tries to generate a preview or flag commercials that you see errors (log excerpts below).

It is probably worth mentioning that this happens on known working channels; that is, my lineup does not include channels that I don’t get. Tuning and recording on the Firewire input and the unencrypted digital input both work with no problems. This problem only happens on the analog input which is controlled by the Firewire channel changer.

I am running several inputs off of the same cable; I wonder if this could be somehow connected to the problem. The cable splits before the STB, and one end goes to a digital encoder card that grabs unencrypted channels. Then I run the cable out (analog) from the STB to the PVR 150. And I also created a Firewire input, which gets all of the (very few) channels that aren’t copy protected. Since the Firewire and the cable out from the STB are sharing the same tuner, I created an input group for them, which I believe will prevent the system from allowing anyone to use the two of them simultaneously.

On the theory that maybe the signal needed a little time to “settle in” after changing channels, I tried adding a call to sleep for five seconds to sa3250ch just before it returns, but this hasn’t helped.

Below is an excerpt from mythbackend.log, showing a typical incident. The system does what looks like a successful recording of “Journal Hoje” on channel 512 at 12:15. But when the show ends at 12:45 and the system tries to run mythbackend –generate-preview, it segfaults. The whole incident log, with the complete memory map, is here: http://pastebin.com/8yRrE7Ny

2010-03-06 12:14:00.731 Reschedule requested for id 0.
2010-03-06 12:14:16.401 Scheduled 662 items in 15.6 = 0.00 match + 15.64 place
2010-03-06 12:14:16.407 scheduler: Scheduled items: Scheduled 662 items in 15.6 = 0.00 match + 15.64 place
2010-03-06 12:14:29.569 TVRec(9): ASK_RECORDING 9 29 0 0
2010-03-06 12:14:30.395 TVRec(10): ASK_RECORDING 10 29 0 0
2010-03-06 12:15:02.771 TVRec(10): Changing from None to Watching RecordingOnly
2010-03-06 12:15:02.776 TVRec(10): HW Tuner: 10->10
2010-03-06 12:15:03.036 ret_pid(30851) child(30851) status(0x0)
2010-03-06 12:15:03.037 External Tuning program exited with no error
2010-03-06 12:15:03.318 AutoExpire: CalcParams(): Max required Free Space: 1.0 GB w/freq: 15 min
2010-03-06 12:15:03.354 Started recording: Jornal Hoje: channel 3512 on cardid 10, sourceid 3
2010-03-06 12:15:03.376 scheduler: Started recording: Jornal Hoje: channel 3512 on cardid 10, sourceid 3
2010-03-06 12:17:02.006 MainServer::ANN Monitor
2010-03-06 12:17:02.007 adding: myth as a client (events: 0)
2010-03-06 12:17:11.045 AutoExpire: CalcParams(): Max required Free Space: 1.0 GB w/freq: 15 min
2010-03-06 12:32:11.239 AutoExpire: CalcParams(): Max required Free Space: 1.0 GB w/freq: 15 min
2010-03-06 12:32:11.336 Expiring 815 MBytes for 3512 @ Fri Mar 5 19:15:00 2010 => Jornal Nacional
2010-03-06 12:32:11.379 autoexpire: Expiring Program: Expiring 815 MBytes for 3512 @ Fri Mar 5 19:15:00 2010 => Jornal Nacional
2010-03-06 12:43:42.907 UPnpMedia: BuildMediaMap VIDEO scan starting in :/var/lib/mythtv/videos:
2010-03-06 12:43:42.983 UPnpMedia: BuildMediaMap Done. Found 87 objects
2010-03-06 12:45:00.310 TVRec(10): Changing from Watching RecordingOnly to None
2010-03-06 12:45:00.342 Finished recording Jornal Hoje: channel 3512
2010-03-06 12:45:00.351 scheduler: Finished recording: Jornal Hoje: channel 3512
2010-03-06 12:45:00.368 Reschedule requested for id 0.
2010-03-06 12:45:00.491 Unknown type, recording width was 0
2010-03-06 12:45:00.853 Finished recording Jornal Hoje: channel 3512
2010-03-06 12:45:02.920 mythbackend version: branches/release-0-22-fixes [22594] www.mythtv.org
2010-03-06 12:45:02.922 Using runtime prefix = /usr
2010-03-06 12:45:02.922 Using configuration directory = /home/mythtv/.mythtv
2010-03-06 12:45:02.938 Empty LocalHostName.
2010-03-06 12:45:02.938 Using localhost value of myth
2010-03-06 12:45:02.939 Testing network connectivity to '192.168.1.163'
2010-03-06 12:45:03.019 New DB connection, total: 1
2010-03-06 12:45:03.024 Connected to database 'mythconverg' at host: 192.168.1.163
2010-03-06 12:45:03.024 Closing DB connection named 'DBManager0'
2010-03-06 12:45:03.026 Connected to database 'mythconverg' at host: 192.168.1.163
2010-03-06 12:45:03.030 Current MythTV Schema Version (DBSchemaVer): 1244
2010-03-06 12:45:03.033 New DB connection, total: 2
2010-03-06 12:45:03.053 Connected to database 'mythconverg' at host: 192.168.1.163
2010-03-06 12:45:03.174 [mpeg2video @ 0x13016c0]Warning MVs not available
2010-03-06 12:45:06.572 Scheduled 661 items in 6.2 = 0.00 match + 6.19 place
2010-03-06 12:45:06.577 scheduler: Last message repeated 1 times: Finished recording: Jornal Hoje: channel 3512
2010-03-06 12:45:06.582 scheduler: Scheduled items: Scheduled 661 items in 6.2 = 0.00 match + 6.19 place
2010-03-06 12:45:08.151 AFD: Opened codec 0x9415390, id(MPEG2VIDEO) type(Video)
2010-03-06 12:45:08.152 AFD: codec MP2 has 2 channels
2010-03-06 12:45:08.153 AFD: Opened codec 0x940ff70, id(MP2) type(Audio)
2010-03-06 12:45:08.538 [mpeg2video @ 0x13016c0]Warning MVs not available
2010-03-06 12:45:08.544 [mpeg2video @ 0x13016c0]Warning MVs not available
*** glibc detected *** /usr/bin/mythbackend: double free or corruption (out): 0x0948dbd8 ***
======= Backtrace: =========
/lib/tls/i686/cmov/libc.so.6[0x61d1ff1]
/lib/tls/i686/cmov/libc.so.6[0x61d36f2]
/lib/tls/i686/cmov/libc.so.6(cfree+0x6d)[0x61d67cd]
/usr/lib/libmythavcodec-0.22.so.0(ff_parse1_close+0x14)[0x10e2834]
======= Memory map: ========
00110000-001a8000 r-xp 00000000 08:03 9729027    /usr/lib/libmythavformat-0.22.so.0.22.0
001a8000-001ab000 r--p 00097000 08:03 9729027    /usr/lib/libmythavformat-0.22.so.0.22.0
…

Thank you!

Larry

[blackoper]

I havn't run into that proble. but I use the 6200ch script for motorolla boxes. I do remember reading somethign where people were adding pauses after the channel change command to give the box time to "settle in". I'll see if I can find any threads on it