Allwinner H3 (and potentially others): left / right audio channels swapped in HDMI signal

daten · December 15, 2019 at 10:53 AM

On Allwinner H3 the left / right channels are swapped when playing audio via HDMI.

In my 4.0 setup that's the case for all channels (front + rear/back).

daten · December 15, 2019 at 11:42 PM

Additional info: when running "speaker-test" with "-c 2" everything is correct (front left and right)

However when started with "-c 4" front left and right are swapped.

**jernej** · December 22, 2019 at 11:39 AM Official Post

daten Sorry for late response. Can you test this update? libreelec-h3.arm-9.80-devel-20191222122600-3fa9671.tar

daten · December 31, 2019 at 1:29 AM

Hey jernej - thanks and sorry for the late reply.

I exchanged the H3 board (OrangePi One) with an H6 board (OrangePi 3) - where the issue also occurs.

As both installations are custom builds (unpatched though, latest master), could you provide a diff? With a respective patch file I could apply it on the currently installed H6 based board (as well) and tinker around myself.

**jernej** · December 31, 2019 at 7:35 AM Official Post

Yes, I just removed LibreELEC.tv/0003-hdmi-improvements.patch at master · LibreELEC/LibreELEC.tv · GitHub

daten · December 31, 2019 at 9:30 AM

I already did so myself which unfortunately didn't improve the situation

**Kwiboo** · December 31, 2019 at 10:22 AM

Hum, ASoC: hdmi-codec: reorder channel allocation list - Patchwork is the upstream submitted patch that have some more details in commit message. It is intended to fix wrong speaker channel allocation mainly for 7.1 audio, where 6.1 ca gets selected without that patch.

daten please share a kodi debug log, it should include some details on how channels is mapped.

Also try to see if setting speaker count in kodi settings to 4.0, 4.1 or 5.1, 7.1 makes any difference.

daten · December 31, 2019 at 1:12 PM

Thanks, will do so ASAP. But I don#t see how it's kodi related, as the same behaviour is observed with `speaker-test`

**Kwiboo** · December 31, 2019 at 4:31 PM

Last time I tested speaker-test (months ago) it did not support or made use of channel mappings api and expect channels to follow a specific configuration / order.

Kodi make use of the channel mapping api when correct alsa card/device is used, make sure you select the hdmi audio device that read and make use of ELD, it usually contain short TV/AVR manufacture name in kodi.

daten · December 31, 2019 at 4:59 PM

Correction: On H6 channels within Kodi appear to always be reversed, whether I set 2.0 or 4.0 as speaker config

For speaker-test it's the same as described though (2.0 correct, 4.0, 5.1, 7.1 incorrect).

~~What I can say for sure so far: Kodi in 2.0 and 4.0 configuration behaves the same way as speaker-test - meaning, 2.0 is correct, while 4.0 is reversed.~~
Within kodi I tested that with a surround test video which addresses the speakers connected to my amp correctly when being played via my notebook.

codekipper · January 1, 2020 at 7:13 PM

I've tested this and it seems to fix the issue...can you confirm?

Comparing LibreELEC:master...codekipper:audiofix · LibreELEC/LibreELEC.tv · GitHub

daten · January 1, 2020 at 10:44 PM

Confirmed - thank you!

codekipper · January 2, 2020 at 7:37 AM

Thanks...I'll prepare a pull request.