HD recording with HDPVR is sporadic and unreliable.

[fract4l]

I have notice over the past 2 weeks that I have problems with recordings were they tend to crash randomly.

I'm running sagetv with a hdpvr under linux. I think my problems come from recording HD. I have a comcast 6200 box right now. Something is halting the recordings and I'm really unable to verify what the problem may be. The sagetv recording eventually seems to start recording again for whatever reason after having slept for a random period of time. For instance "Trust Me" from last Monday looks like this for me

TrustMe-AuCourant-149112-1.ts ~ 900MB
TrustMe-AuCourant-149112-0.ts ~ 1.9GB

Attached you will find the debug output from the sagetv server during the recording of the show. There are parts missing to the show in between those recordings as my recording settings should have an hour of video at 3.7GB.

Before I contacted support directly I wanted to see if anyone else was having a similar problem with an hdpvr. Unfortunately this doesn't seem to happen with any pattern that I can tell.

I'm so close to having this setup work perfectly if only I could get entire recordings before adding more STB's and HDPVR's!

[LittleJohnny]

Have you ever been able to record files that were greater than 2GB?

I assume your problem is related to your version of Linux. Many 32-bit linux versions have 2GB file limits. You might be able to run a different type of filesystem to get around the limit. Check the support site of the version of Linux you are running for the details.

[fract4l]

Thanks for the reply. I guess I should have mentioned I am using ubuntu 8.10 which by default uses a kernel > 2.4 and glibc > 2.2 both of which, if I'm not mistaken, eradicated the annoyance of not allowing files to being grater than 2GB. I'm using also using ext3 which worst case has a 16GB file limit with the details mentioned in the previous sentence.

To answer in a much easier way. Yes I do have a number of full complete hour recordings at ~4GB. I even have a few complete 2hr movies that weigh in at almost 8GB.

[bcjenkins]

Care to post a dmesg output too? Might not hurt to post your fstab as well.

B

[fract4l]

I know it's been a while since starting this, and I still haven't come up with any good information or possible reasons. In fact 15 minutes ago I noticed the red light light up on my hdpvr in the middle of when it should have been recording "Two and Half Men". I checked the logfile and results were pretty much the same as the the show I attached a log file above. I wonder why sagetv doesn't recognize right away the thread died and try to restart it instead of sleeping away for x number of minutes.

I checked my kernel.log and there were no new for the past 3 days, so that won't be much help there.

I thought it might have been problems with the optical audio, but I have updated the newest firmware as of the 15th of march, that didn't help. I also started using the rca audio yesterday in hopes that it would solve my problem but obviously that is not the case.

Below you will find the fstab from my machine.

# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
# /dev/sda1
UUID=463d12b8-5e55-4fd9-9676-64634f069b39 /               ext3    relatime,errors=remount-ro 0       1
# /dev/sda5
UUID=f0ba715a-8c90-4368-8a31-863b100bf8d6 none            swap    sw              0       0
/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto,exec,utf8 0       0

One thing I have noticed with my hdpvr and my comcast STB is that if I change the channel during my recording (this was part of my testing) the recording will die. Then sagetv will sleep for x number of minutes and then at some point, what that point is I'm not sure, sagetv notices that it's not recording and it tries to start the recording the same show/channel again. The problem is that 10 minutes or so has passed where the program wasn't recording, which in my book is unacceptable. The causes of the two problems are not the same, but they do share similar outcomes. Just thought I'd point that out.

[fract4l]

So I think I've narrowed down why the recordings stop. I am able to reproduce the error each and every time now.

I recorded with my comcast stb dvr an episode of TV a few days ago as I normally do since my hd-pvr doesn't always work, due to the problem listed above. I watched the episode on my dvr and noticed there was a pop in the audio feed once a local news/weather commercial started. I assume the feed changed audio sources or maybe how it was broadcasting the audio changing from 5.1 to stereo or visa versa.

I went and checked the outputs from my sagetv recording and the recording died as soon as the this local news commercial started. Now I'm not sure this is a problem with sagetv per se because if I play back this recorded hour while doing a manual recording

cat /dev/video > ~/test.ts

As soon as the commercial starts it will stop capturing. It does not affect the device (/dev/video0) so the OS will continue with the cat, but the red light on the hd-pvr has turned off. It does not however affect the playback of the video. I am still able to watch and listen to the show with only hearing a pop of the audio.

[bcjenkins]

Do you have a windows box to attach the hdpvr to for a driver/firmware update? I am on version 0xf I think. Also, I am recording analog stereo because of issues with FiOS boxes. Lastly, have you compiled a driver from source yet?

B

[MrD]

Based on your fstab it looks like you have a single hard drive / partittion.

Personally, I would use a separate hard drive for the recording device. If that is not possible, at a minimum a different partition.

Also, I would use an xfs filesystem instead of ext3.

fyi, I have also noticed lock-ups with the HD-PVR on audio changes; I am using XP though.

[MrD]

Originally Posted by MrD

Also, I would use an xfs filesystem instead of ext3.

For the recording device I mean

[fract4l]

So I've let the hd-pvr run for a week now using rca for audio instead of spdif without touching anything. I'm happy to say that at this point I haven't had a fragmented recording. I guess I will have to leave it this way for the time being.

The only problem I'm finding now is the that audio levels from the RCA are too low to listen to via passthrough or streaming the recording with placeshifter. The only way I have been able to hear the audio is after encoding it again with ffmpeg using a -vol 4000.

Obviously this isn't the best solution as encoding video takes a number of hours. So I guess I need to see if there is a way that I can get sagetv to increase the volume at recording time. Initial searches didn't return anything fruitful but I'll continue looking.

Almost there!

[MrD]

Originally Posted by fract4l

The only problem I'm finding now is the that audio levels from the RCA are too low to listen to via passthrough or streaming the recording with placeshifter. The only way I have been able to hear the audio is after encoding it again with ffmpeg using a -vol 4000.

This is a bit of a hack, but maybe you could feed the RCA into a old receiver (with a tape monitor) then feed the HD-PVR with the tape monitor outputs.

[troll5501]

Originally Posted by fract4l

So I think I've narrowed down why the recordings stop. I am able to reproduce the error each and every time now.

I recorded with my comcast stb dvr an episode of TV a few days ago as I normally do since my hd-pvr doesn't always work, due to the problem listed above. I watched the episode on my dvr and noticed there was a pop in the audio feed once a local news/weather commercial started. I assume the feed changed audio sources or maybe how it was broadcasting the audio changing from 5.1 to stereo or visa versa.

I went and checked the outputs from my sagetv recording and the recording died as soon as the this local news commercial started.

I know I'm reviving an old thread, but I've discovered this exact same behavior in my SageTV Linux environment. Did you ever find a solution or did you just stay with the RCA analog audio input?

In my case it's the local Comcast low-quality commercials that seem to kill the HDPVR stream. The moment the commercial is over, the recorder stops. As in your case, Sage detects this and restarts the recorder each time. But I don't recall ever seeing this when I was using Sage under Windows so it's making me think it's a Linux driver issue.

[Skirge01]

This is a known issue with the chip used in the HD-PVR. I've blogged about it, as well as posted my findings here on the forums. The actual issue normally traces back to a single channel switching from stereo to 5.1, which requires the HD-PVR's chip to stop and restart to change the audio format.

[troll5501]

What's strange to me is that I was running this same HDPVR under Windows for at least six months using SPDIF. While I had occasional lockups like many others, I didn't notice this behavior with it stopping due to apparent audio stream changes. I typically record sporting events and they were always one file without breaks. Now I end up with 10 to 20 files for a single game under Linux.

So far in Linux the HDPVR does not seem to lock up, but now I have this "new" problem.

[Skirge01]

You may have had other issues which were masking the "simple" audio switch issue. That was also the last "issue" I identified because it was finally the ONLY thing that was going wrong. Sadly, it's not one that anyone can fix. Thankfully, this is not a major issue and doesn't prevent the HD-PVR from recording the show or from recording the next show. But, it does cause the multi-file issue which Sage happens to handle quite elegantly. TBH, I don't even consider it an issue anymore.