Audio Stutter on new AAC?

Original Post to Kodi on Reddit here: https://www.reddit.com/r/kodi/comments/gmgk7l/kodi_audio_stutters_playing_aac_audio/

They told me to post to CoreELEC, though I was mostly looking for assistance on troubleshooting and they shot it down pretty quick. It might be Kodi but i’m unsure…

In short, EVERY new episode of Rick and Morty that got added, the audio would stutter. It stops playing every 15-30 seconds for like 2 seconds, then continues for the entire episode. I have no idea why, because playback on my phone, browser, or even the Samsung native Plex app would play back the file perfectly fine.

It was only my 2 Odroid N2’s running the latest version of CoreELEC (9.2.2)

I did snag some of the media info of the ones that were having issues, comparing to other AAC files that it plays just fine.

This first file plays just fine.

Audio #1
ID                                       : 1
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : mp4a-40-2
Duration                                 : 21 min 16 s
Bit rate mode                            : Variable
Bit rate                                 : 124 kb/s
Maximum bit rate                         : 210 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 46.875 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 18.9 MiB (2%)
Language                                 : English
Default                                  : Yes
Alternate group                          : 1
Encoded date                             : UTC 2020-05-11 07:46:35
Tagged date                              : UTC 2020-05-11 07:47:21

This second file is the one that is having issues, obviously a different codec ID, can anyone confirm that this ID is supported? Maybe its a new model and my receiver(s) don’t support it?
Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : A_AAC-2
Duration : 22 min 35 s
Bit rate : 126 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 44.1 kHz
Frame rate : 43.066 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 20.3 MiB (3%)
Title : English
Language : English
Default : Yes
Forced : No

Troubleshooting steps. I have completely uninstalled and re-installed CoreELEC with no luck. I even installed older version to rule out any recent changes and it doesn’t appear to have any effect on it at a all. I’m able to run 4K HDR with TrueHD on both setups, they are GB ethernet connected directly to the server on LAN, so I don’t believe network issues are an issue here. I have also changed input to 2 channel and not pass through the audio etc… (to try and rule out the receivers) and it is still doing it. I’m thinking of testing the audio and forcing it to transcode??

Any assistance to further troubleshoot would be awesome, I would love to figure it out :smiley:

Update, I think I figured it out in case anyone else runs into the same issue.

There is a setting I changed.
Settings > System > Audio > Audio output device >

Changed
Old: ALSA: AML-AUGESOUND,HDMI Multi Ch PCM
New: ALSA: AML-AUGESOUND,HDMI

I’m not sure how this got changed, I’m thinking the updated to 9.2.2 may have changed it? Regardless this fixed my issue, i’m goin with the fact my receiver may not fully support it. Hope it helps seomone!

2 Likes

Thanks, this sorted out my AAC stutter.