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Running version 16.1 on a Zotac Zbox. Connected via HDMI Kodi (Zotac Zbox) ----> Pioneer receiver -----> Panasonic TV. I have always gotten audio drop-outs while playing a video with AAC audio. I'm not sure if it happens with 2 channel audio but definitely with 5,1. My receiver is able to decode AAC & displays "PCM" while doing so. All other audio is fine & this has always been an issue, just now taking a shot at fixing it. Any help is appreciated.

http://pastebin.com/embed_js/kjwnk33L
(2016-12-26, 11:08)jz1276 Wrote: [ -> ]Running version 16.1 on a Zotac Zbox. Connected via HDMI Kodi (Zotac Zbox) ----> Pioneer receiver -----> Panasonic TV. I have always gotten audio drop-outs while playing a video with AAC audio. I'm not sure if it happens with 2 channel audio but definitely with 5,1. My receiver is able to decode AAC & displays "PCM" while doing so. All other audio is fine & this has always been an issue, just now taking a shot at fixing it. Any help is appreciated.

http://pastebin.com/embed_js/kjwnk33L


Have you confirmed it's not your receiver's buggy implementation of certain encoding modes? I'm sure you're aware but AAC comes in many flavours and not just channel layout, by making Kodi do the decoding to PCM or transcoding to dolby digital before output over HDMI?
I've just done a search through the manual for your receiver Pioneer VSX-1122 and it states it is compatible with AAC but not with 5.1 and also has a max bitrate.
2 channel only, no SBR, 320kbps max bit rate
https://www.pioneerelectronics.com/PUSA/...STRUCTIONS
Do a search for AAC in the pdf download and it gives a grid on what is supported.
No known amp decodes aac 5.1, and kodi does not pass it through. It converts to PCM.
(2016-12-26, 11:40)robo989 Wrote: [ -> ]I've just done a search through the manual for your receiver Pioneer VSX-1122 and it states it is compatible with AAC but not with 5.1 and also has a max bitrate.
2 channel only, no SBR, 320kbps max bit rate
https://www.pioneerelectronics.com/PUSA/...STRUCTIONS
Do a search for AAC in the pdf download and it gives a grid on what is supported.

Thanks for the help. Robo just contradicted what you said though. The receiver will output 5.1 aac but like i said, there are dropouts every 20 or so seconds. Could robo be correct in saying kodi is converting the aac to pcm then passing through to the receiver?
Yes of course kodi is transcoding it. It must do so. Whether it transcodes to pcm or to ac3 depends on your settings.
Input: AAC 5.1 -> ffmpeg decode to Float Data -> AE finds a matching sink -> transforms float into 32 bit int (most likely) -> output

If Speaker settings: 2.0 and AC3 Transcode enabled -> AAC 5.1 -> ffmpeg decodes to float -> AEEncoderFFmpeg encode to AC3 -> AESink output as 16 bit int format.
I had a similar problem some time ago. But it wasn't a Kodi issue.
I use Handbrake to encode my movies. And I used AAC 5.1 320kbps (avcodec) for the audio tracks.
Some movies had that audio drops, after I've checked the handbrake logs there were some errors.
This doesn't happen with fdkaac or with lower bitrates and 5.1.
I tried the Nero AAC encoder => no drops
I checked IFME (which suppoerted in an older version hevc video passthrough and just audio encoding) => no drops

If you encoded the videos yourself, check your logs. Maybe it's the same problem.
(2016-12-29, 13:54)3dfx Wrote: [ -> ]I had a similar problem some time ago. But it wasn't a Kodi issue.
I use Handbrake to encode my movies. And I used AAC 5.1 320kbps (avcodec) for the audio tracks.
Some movies had that audio drops, after I've checked the handbrake logs there were some errors.
This doesn't happen with fdkaac or with lower bitrates and 5.1.
I tried the Nero AAC encoder => no drops
I checked IFME (which suppoerted in an older version hevc video passthrough and just audio encoding) => no drops

If you encoded the videos yourself, check your logs. Maybe it's the same problem.

No, I did not encode these movies myself.

What's odd is I remember there used to be an option in this menu "AAC capable receiver" which is no longer there. I actually don't see any options for AAC audio at all anymore. Did anyone check out the debug log? Does everything look ok?

Image
There are no aac capable receivers in this context (I am not sure how many times I have to say this). So the option is no longer there.
There was this Entry. But there was no code :-) - we removed it.
(2016-12-30, 07:04)nickr Wrote: [ -> ]There are no aac capable receivers in this context (I am not sure how many times I have to say this). So the option is no longer there.


OK, no need to get upset!