Bug #1928
No Audio on recordings (mkv)
0%
Description
Hi,
I know there are several tickets around which discuss this problem, but none of them is in progress as I can see, and none of them had a solution as far as I know. But this problem persists till now. Every time I try to record some movies from live tv there is no audio included in mkv:
Jan 11 23:48:06 services tvheadend[24739]: dvr: /htpc/videos/recordings/Der Blade Runner.mkv from adapter: "Tuner 2 (DVBSky S952 PCI)", network: "ASTRA 1", mux: "ASTRA 1: 10,832,250 kHz Horizontal (No satconf)", provider: "BetaDigital", service: "RTL2 HD" Jan 11 23:48:06 services tvheadend[24739]: dvr: # type lang resolution aspect ratio sample rate channels Jan 11 23:48:06 services tvheadend[24739]: dvr: 1 TELETEXT <disabled, no valid input> Jan 11 23:48:06 services tvheadend[24739]: dvr: 2 H264 1920x1088 30:17 Jan 11 23:48:06 services tvheadend[24739]: dvr: 3 AC3 ger ? ? <disabled, no valid input> Jan 11 23:48:06 services tvheadend[24739]: dvr: 4 CA Jan 11 23:48:06 services tvheadend[24739]: dvr: 5 CA Jan 11 23:48:06 services tvheadend[24739]: dvr: 6 CA Jan 11 23:48:06 services tvheadend[24739]: dvr: 7 CA Jan 11 23:48:06 services tvheadend[24739]: dvr: 8 CA
Live tv (OpenELEC 3.2.4, XBMC) works (always) well, only on recording a channel this problem exists.
This always seems to happen if teletext is listed before audio channel. I tried this on Xubuntu 12.04 with stable and beta from your repository.
What should/can I do? I think the problem is well known, but I did not find a solution for this till now.
Thank you very much.
History
Updated by Adam Sutton almost 11 years ago
Short term solution, record using TS (passthru). It's a much safer option in general. You can always remux to MKV (as I do) later on.
As for the actual issue, no idea at this stage. Are there channels that are consistently a problem?
Adam
Updated by Johann Reisner almost 11 years ago
How do you remux, by post-processing or manual? I would not like to do this manually, if there's a chance to automate this in a good working way. On german RTL2 HD there it happens very often, can't say which channels have this problem, but most of the others work well (till now). I don't know if this was random, but it seemed, that recordings at night are very often without audio. I gave a few schedules a try random at daytime, but there were no problem. But what I can say is, that my wife watched a program yesterday at night via xbmc which had audio. We recorded the same program which had no audio.
Updated by Adam Sutton almost 11 years ago
I remux manually, but then I also cut top/tail, so that takes more time than calling (and running) ffmpeg to remux But to be honest, I don't keep a lot of what I record.
But you could indeed run a post-proc script to do it automatically.
I could really do with a sample file (TS passthru recording etc...) of one of the shows that fails. Do you know if it happens to coincide with the channel changing its audio stream? Maybe from 2.0 to 5.1 or visa versa?
Adam
Updated by Johann Reisner almost 11 years ago
I don't think it's a problem of changing audio stream, because I run 10 mins before and after a recording. So it's nearly impossible to get exact a part of the move where the audio changes. The movie I mentioned above e.g. started recording in the show before, where definitely had an ac3 5.1 without changing this the next 5 minutes or so. Isn't there an ugly possibility to check the audio stream lets say 3 times or so? I think the possibility to find the working audio should be a lot higher. I'm wondering why this seems to happen only at night. Looks like a failing wake up from standby of the tuner or something like that. That's only a guess, but who knows....
Could you guide me a little bit where to find the part of the source code? Maybe I will dig a little and try something out, maybe I'm lucky to find anything which could help you to solve the problem...
Updated by Jeff Clark over 10 years ago
Ran into this problem today myself. Been using for about a year and this is the first time it's happened. Will switch to TS recording to hopefully catch the same thing again.
2014-02-24 21:01:07.564 [ INFO] dvr: /media/The Blacklist.2014-02-24.16.mkv from adapter: "HDHomeRun ATSC 103C1101-0 : ATSC #0", network: "Chicago OTA", mux: "563028", provider: "<N/A>", service: "NBC5 " 2014-02-24 21:01:07.564 [ INFO] dvr: # type lang resolution aspect ratio sample rate channels 2014-02-24 21:01:07.564 [ INFO] dvr: 1 MPEG2VIDEO 1920x1080 16:9 2014-02-24 21:01:07.564 [ INFO] dvr: 2 AC3 eng ? ? <disabled, no valid input> 2014-02-24 21:01:07.564 [ INFO] dvr: 3 AC3 spa 48000 2
Just a guess, but doesn't AC3 A/52 support channel switching mid-stream? I've definitely seen it switch from 5.1 to 2.0, which makes me think 0 is possible also.
Updated by Johann Reisner over 10 years ago
Jeff Clark wrote:
Just a guess, but doesn't AC3 A/52 support channel switching mid-stream? I've definitely seen it switch from 5.1 to 2.0, which makes me think 0 is possible also.
I do not think it's a problem with audio switch, because this happens so often, that the chance I always get exactly the period on which audio was switched is nearly 0 I think. And if I got it at a switching period, shouldn't the audio track be displayed as 2.0?
But maybe it could be possible, I really don't know...