Short recordings, possibly after ad-detection

Channels DVR Server
#1

Hi All,

I am observing some cases of recordings which end up very short or corrupt, normally just a couple of mins for a program that may be well in excess of an hour. I suspect this may be due to ad-detection, but I have more testing to do now with it turned off.

An example from my logs:-

2025/11/17 01:33:01.786330 [DVR] Waiting 23m58s until next job 1763344620-ch83 Night Watch (1995)
2025/11/17 01:57:00.003031 [DVR] Starting job 1763344620-ch83 Night Watch (1995) on ch=[83]
2025/11/17 01:57:00.577618 [TNR] Opened connection to 1250E143/1 for ch83 Together TV
2025/11/17 01:57:00.577902 [DVR] Recording for job 1763344620-ch83 from 1250E143 ch83 into "Movies/Night Watch (1995) 2025-11-17-0157.mpg" for 2h5m59.996885429s
2025/11/17 01:57:02.511414 [IDX] Generating video index for job 1763344620-ch83
2025/11/17 03:21:59.235515 [SYS] Created database snapshot: backup-20251117.032158
2025/11/17 03:21:59.235758 [SYS] Removing old backup backup-20251021.005239
2025/11/17 04:03:00.013517 [TNR] Closed connection to 1250E143/1 for ch83 Together TV
2025/11/17 04:03:00.440071 [SNR] Signal statistics for "Movies/Night Watch (1995) 2025-11-17-0157.mpg": ss=100% snq=99%,80%-100% seq=100% bps=68900,22560-76704 pps=33,9-41
2025/11/17 04:03:00.785924 [SNR] Buffer statistics for "Movies/Night Watch (1995) 2025-11-17-0157.mpg": buf=0% drop=0%
2025/11/17 04:03:00.786194 [DVR] Finished job 1763344620-ch83 Night Watch (1995)
2025/11/17 04:03:02.074322 [DVR] Processing file-1515: Movies/Night Watch (1995) 2025-11-17-0157.mpg
2025/11/17 04:03:03.881143 [DVR] Generating fingerprint for file-1515: Night Watch (1995) 2025-11-17-0157.mpg
2025/11/17 04:03:04.274065 [ERR] Generating fingerprint failed for file-1515: could not write MFCC: ffmpeg failed: exit status 1: [out#0/f32le @ 0xb4ce640] Output file does not contain any stream

No Keyframes were found in the stream
2025/11/17 04:03:04.366398 [DVR] Running commercial detection on file 1515 (Movies/Night Watch (1995) 2025-11-17-0157.mpg)
2025/11/17 04:03:04.398788 [DVR] Commercial detection failed for Night Watch (1995) 2025-11-17-0157.mpg: exit status 255: Comskip 0.82.011, made using ffmpeg
Donator build
/volume1/ChannelsDVR/Movies/Night Watch (1995) 2025-11-17-0157.mpg: could not open video codec

The resulting MPG file was 56,610KB and would not playback.

Any advice would be appreciated.

If this is an ad-detection issue, it would be a nice feature perhaps to disable ad-detection on certain channels only... At the moment it appears its either on for all channels or off.

#2

@sceptic101
Is it a UK FTA channel?
What does Channels DVR show for the details of the recording.
Options > View Details

Screenshot 2025-11-19 at 10-58-38 Channels Manage Recordings
Screenshot 2025-11-19 at 10-58-38 Channels Manage Recordings798×496 32.7 KB

#3

Yes this is from a UK FTA channel. Unfortunately I wiped all the corrupt/short recordings I could find last night so I am unable to check the recording details now. Since I turned off Ad-detection I not had another corrupt/short recording, but will need a few more days of testing to see if this fixes it definitively or not.

#4

Ok having done some further testing this issue appears to be signal related, for example..

2025/11/26 03:43:00.406394 [SNR] Signal statistics for "Movies/Dark Prince The True Story of Dracula (2000) 2025-11-26-0147.mpg": ss=100% snq=95%,0%-100% seq=43%,0%-100% bps=1239493,428640-3150880 pps=130,44-283 sigerr=97%
2025/11/26 03:43:00.790167 [SNR] Buffer statistics for "Movies/Dark Prince The True Story of Dracula (2000) 2025-11-26-0147.mpg": buf=0% drop=0%

I'm hoping someone can give me some pointers. My aerial was only recently fitted and I've not had issues till this one. I am assuming ss=signal strength, and sq=signal quality. The numbers above don't seem that bad, yet apparently 97% of the recording was impacted by signal issues.

I have other recordings on different channels that appear to have worse values but have zero errors, so I think there is more to this than meets the eye.

2025/11/25 22:03:00.830443 [SNR] Signal statistics for "TV/Cooper & Fry/Cooper & Fry S01E02 2025-11-25-1957.mpg": ss=100% snq=61%,0%-73% seq=99%,0%-100% bps=3472683,1176128-17428352 pps=297,102-1492
2025/11/25 22:03:01.886646 [SNR] Signal statistics for "TV/Summerwater/Summerwater S01E06 The Fire 2025-11-25-2057.mpg": ss=99%,0%-100% snq=60%,0%-69% seq=99%,0%-100% bps=3685923,1228768-13349504 pps=315,105-1143
2025/11/25 22:03:02.006056 [SNR] Buffer statistics for "TV/Cooper & Fry/Cooper & Fry S01E02 2025-11-25-1957.mpg": buf=0%-2% drop=0%

Any advice appreciated.

#5

Together TV is not full-time on Freeview channel 83, but the EPG shows the full 24h.

According to: https://www.togethertv.com/troubleshooting-watching-together-tv-freeview

As of 20th March 2024, Together TV's Freeview coverage changed on channel 83. We are only available between 18.00-00.00 everyday.

Dave

#6

Silicon Dust can help you.
Post in their forum here HDHomeRun Setup & Troubleshooting - Silicondust
They will most likely want to see diagnostics logs from your tuner, see this post for what they'll request
HDHomerun 4K Local Stations in New Jersey - Silicondust

#7

@hillcroftdave Thanks for pointing that out, I had not realised. It would be a lot less confusing if they updated their guide data to reflect that.