AAC 2.0 sound is sometimes "slow motioned" on Vero 4K+

Help and Support Vero 4K / Vero 4K +
1

Hey all,

I’m facing a weird issue with my Vero 4K+ and reading file with AAC 2.0 sound.

after a reboot, or a power off, when I play these files (mostly my kids episodes), the video plays fine, but the sound is “slowed down” (not the volume level, the track itself is slowed down, a bit like a laggy track or a slow motion for the sound, not sure how to express that) , which make the file unwatchable.

Files with sound encoded in Dobbly digital will play just fine.

My setup is like this :

  • Vero 4K+ (resolution set at 1080p)
  • I’ve set a restricted profile for my kids, but issue seems to be present in the main profile as well
  • sound goes via HDMI to the TV
  • TV is plugged with an optical cable to a Cambridge Topaz SR20 amplifier
  • Files are stored on a Synology NAS mounted via nfs with autofs

Now, the very weird thing is that for un unknown reason, at some point, it will start working just fine and I will be able to play these files with the sound being absolutely normal.

For example, yesterday morning, files with AAC 2.0 were playing just fine and, this morning, without anything changed (no reboot, usual shutdown of the amplifier,..), the sound wouldn’t work.

Then, one day, the sound will start to “slow motion’“ again.

I’ve searched on the forum but haven’t found anything similar.

Would someone have an idea ?

Thanks!

MathFly_

2

I’ve uploaded the logs from MyOSMC :
paste.osmc.tv/yiroxecoye

This morning, I had trouble playing some files (Billy.Le.Hamster), I tries multiple config changes, but oculd not get it to work.

I launched some episodes with dobly digital. Then I turned off (put to sleep, haven’t removed the plug) the TV and the amplifier while leaving my Vero 4K+ on.

Just 5 minutes ago, I turned TV and amplifier back on, started the same episode and that played just fine.

That is when I’ve generated the logs.

3

I cant’ find much difference in the logs of today around 10:30 and around 12:30 :confused:

I’m starting to wonder if the issue would come more from the TV than the OSMC, but when AAC files won’t play well, Dobly digital files will play just fine. it’s limited to that format.

4

In case the Philips TV has its own speakers (I’m guessing it does), can you reproduce the problem when the sound is played through the onboard speakers?

There is a small discrepancy here. These are the audio capabilities of you TV;

====================== Audio Cap =================== k3dRrf31
CodingType MaxChannels SamplingFreq SampleSize
PCM, 2 ch, 32/44.1/48/88.2/96 kHz, 16/20/24 bit
AC-3, 6 ch, 32/44.1/48 kHz, MaxBitRate 640kb/s
DTS, 6 ch, 32/44.1/48 kHz, MaxBitRate 1536kb/s

But you configured a default of

Dolby Digital (AC3) capable receiver: true
Enable Dolby Digital (AC3) transcoding: true

DTS capable receiver: true
Dolby Digital Plus (E-AC3) capable receiver: true

Number of channels: 2.1 ===> Default: 2.0

    <setting id="audiooutput.channels">2</setting>

Which means here in this context everything which is not in AC3 or DTS audio format will be transcoded to AC3 or a 3(!!!) channel PCM (2.1 speaker setup).

I suggest to correct settings

  • Use a default Audio Number of Channels: 2.0
  • E-AC3 ist not listed in the audio caps of the Philips device (would be Dolby_Digital+ or so in the audio caps); disable this passsthrough feature in the audio settings

Not sure whether these have any influence on the behaviour you see.

5

Thanks for you reply.

The TV speaker are disabled and all the audio is sent to the Cambridge amplifier which is a 2.1 receiver (2 channel + Sub), that’s why I set 2.1 for the audio channel.

The thing is that, the issue is not always happening, and I don’t change the audio settings at all.
Most of the time, it will play fine, and sometimes, it fail and produce a slow motioned sound.

That’s why I don’t understand the issue. I can’t link it to something that was changed or done that could explain why it fails sometimes and an hour later, if I turn the TV and receiver back on, it worked just fine.

For example, yesterday around 10h30, that would fail, I put the TV to sleep and turned off the receiver. Two hours later, I started the TV and receiver, and it worked just fine. I turned the TV back to sleep and turned off the receiver again.
I tried again yesterday evening, and it kept playing just fine.

I can’t identify what’s happening really :frowning:

6

Then change that temporarily so you can run this test. We’ve already invested quite a bit of time looking at the logs, and you don’t have that kind of time to spare?

Typically, a TV can only pass through E-ARC what it itself supports in terms of bandwidth and audio formats. And in this TV’s case, that’s only 2-channel PCM, AC3, and basic DTS.

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8

Sorry if I made it feel I had no time to test that. That is not what I meant with my answer.

I just wanted to explain the current situation and I’m trying to gather element to help understand the issue better as it’s not happening all the time.

I know that analyzing logs is time consuming and I thank you for that.

Next time the issue will appear again, probably in a few days, I will test with the TV speaker to see if the problem occur with it and will let you know.

Thanks again.

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