No audio on random recordings. (maybe TVHeadend problem)

Hello everyone.

Disclaimer: This might NOT be a VERO problem - could be TVHeadend related.
I’m reaching out to this fantastic forum - hoping someone can shed some light on the problem at hand, and point me in the right direction.

TVHeadend is running on a Synology NAS - not the Vero itself.
Recordings are (of course) stored on the NAS as well.
Recording profile is matroska - and reading the TVHeadend forum - it might help switching to pass instead.
However if I do that I no longer can access subtitles for hearing impaired - they are only available with matroska recording profile - so I have to stick to matroska

A HDHomerun tuner is delivering the signal (free to air)

I experience missing audio on random recordings (so far always on the same channel)

I have tried retuning all channels on the HDHomerun to no avail.

Previously I used DVBlink (later Mosaic) - which is now discontinued.
Never had the issue there.

Any suggestions on how to solve this problem?

Here is mediainfo from a problematic recording: (no audio section)

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 45 min 59 s
Bit rate : 8 066 kb/s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 50.000 FPS
Standard : Component
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.175
Stream size : 2.59 GiB (98%)
Language : English
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Text #1
ID : 2
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Language : Danish
Default : Yes
Forced : No

Text #2
ID : 3
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Language : Danish
Default : Yes
Forced : No

Menu
00:00:00.000 : 00:00:00.000
00:00:59.560 : 00:00:59.560
00:31:10.460 : 00:31:10.460

Same channel - audio working

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Format settings, GOP : M=6, N=48
Codec ID : V_MPEG4/ISO/AVC
Duration : 35 min 59 s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 50.000 FPS
Standard : Component
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Language : English
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Audio
ID : 2
Format : AAC LC SBR
Format/Info : Advanced Audio Codec Low Complexity with Spectral Band Replication
Commercial name : HE-AAC
Format settings : Explicit
Codec ID : A_AAC-2
Duration : 35 min 59 s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 23.438 FPS (2048 SPF)
Compression mode : Lossy
Delay relative to video : -5 ms
Language : Danish
Default : Yes
Forced : No

Text #1
ID : 3
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Language : Danish
Default : Yes
Forced : No

Text #2
ID : 4
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Language : Danish
Default : Yes
Forced : No

Menu
00:00:00.000 : 00:00:00.000
00:00:59.540 : 00:00:59.540
00:25:05.020 : 00:25:05.020

As you can see yourself that Video has no Audio Stream. So surely not a OSMC problem. Why TVHeadend didn’t record audio on that video you most likely only can find out with debugging TVHeadend logs.

Alternative if there is a certain channel where the problem occurs maybe record with pass profile to see if there is a specific audio codec that makes problems.

Thanks for your feedback @fzinken
Yeah I guess I will have to dig deeper down into TVHeadend logs to see if I can spot the problem.

It is a specific channel for all that I know - and yeah I could test with ‘pass’ profile in TVHeadend.
Only downside is that I never know when the problem is present - and hence when to troubleshoot.