Hi,
I am trying to make long high quality recordings with a TBS6991 with CI and Smartcard.
This works fine using mumudvb (based on dvblast). However, the stream has bitcorruptions 20-100 times per hour. This leads to visual artefacts in the recording during playback.
Even if I record without any processing, the visual artefacts are there when playing the stream. This is a DVB-S2 8PSK channel
Using szap-s2 we see bit error rate (BER) = 0 all the time.
It looks like there are absolutely no signal problems and we use a very large dish with good quality connectors and relatively short cables.
ffmpeg (decoding the h264) reports errors like
[h264 @ 0x464b420] cabac decode of qscale diff failed at 27 12
[h264 @ 0x464b420] error while decoding MB 27 12, bytestream (2834)
[h264 @ 0x464b420] concealing 1102 DC, 1102 AC, 1102 MV errors in B frame
frame=29605 fps= 25 q=28.0 size= 151183kB time=00:19:44.01 bitrate=1046.0kbits/s dup=39 drop=0
frame=29629 fps= 25 q=28.0 size= 151340kB time=00:19:45.02 bitrate=1046.2kbits/s dup=39 drop=0
[h264 @ 0x48e7480] left block unavailable for requested intra4x4 mode -1 at 0 28
[h264 @ 0x48e7480] error while decoding MB 0 28, bytestream (23933)
[h264 @ 0x48e7480] concealing 409 DC, 409 AC, 409 MV errors in I frame
frame=29657 fps= 25 q=28.0 size= 151465kB time=00:19:46.03 bitrate=1046.2kbits/s dup=39 drop=0
[h264 @ 0x494b240] concealing 941 DC, 941 AC, 941 MV errors in B frame
[h264 @ 0x4a76b80] error while decoding MB 36 35, bytestream (-16)
[h264 @ 0x4a76b80] concealing 58 DC, 58 AC, 58 MV errors in P frame
frame=29680 fps= 25 q=28.0 size= 151570kB time=00:19:47.01 bitrate=1046.0kbits/s dup=39 drop=0
[h264 @ 0x4c06280] left block unavailable for requested intra4x4 mode -1 at 0 6
[h264 @ 0x4c06280] error while decoding MB 0 6, bytestream (59488)
[h264 @ 0x4c06280] concealing 1399 DC, 1399 AC, 1399 MV errors in I frame
frame=29705 fps= 25 q=28.0 size= 151679kB time=00:19:48.02 bitrate=1045.9kbits/s dup=39 drop=0
frame=29728 fps= 25 q=28.0 size= 151779kB time=00:19:49.00 bitrate=1045.7kbits/s dup=39 drop=0
[h264 @ 0x4a76b80] concealing 1045 DC, 1045 AC, 1045 MV errors in P frame
[h264 @ 0x4757d80] concealing 1392 DC, 1392 AC, 1392 MV errors in P frame
frame=29753 fps= 25 q=28.0 size= 151876kB time=00:19:50.06 bitrate=1045.5kbits/s dup=39 drop=0
frame=29777 fps= 25 q=28.0 size= 151984kB time=00:19:51.07 bitrate=1045.3kbits/s dup=39 drop=0
[h264 @ 0x4757d80] left block unavailable for requested intra4x4 mode -1 at 0 15
[h264 @ 0x4757d80] error while decoding MB 0 15, bytestream (53878)
[h264 @ 0x4757d80] concealing 994 DC, 994 AC, 994 MV errors in I frame
[h264 @ 0x48e7480] concealing 430 DC, 430 AC, 430 MV errors in P frame
[mpegts @ 0x246c620] PES packet size mismatch
frame=29805 fps= 25 q=28.0 size= 152139kB time=00:19:52.08 bitrate=1045.5kbits/s dup=39 drop=0
[h264 @ 0x4757d80] concealing 946 DC, 946 AC, 946 MV errors in P frame
frame=29833 fps= 25 q=28.0 size= 152315kB time=00:19:53.08 bitrate=1045.8kbits/s dup=39 drop=0
Sometimes there are absolutely NO problems for 10 minutes. But it's not related to weather, rain, other electrical cables, we tried all that. It happens constantly, every hour, on different cards, tried different satellite dishes and tried different locations.
A regular DVB-S2 set top box has NO visual artefacts on the same coaxial cable connection.
I suspect bits get corrupted in the card or the drivers.
Please advice on how to troubleshoot this issue.