Author Topic: Stereo audio channels swapped?  (Read 2713 times)

Skirmisher

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Stereo audio channels swapped?
« on: August 14, 2020, 01:08:40 pm »
I noticed a good while back (when first starting to use the Blackbird) that the sound card seemed to have the stereo channels in the wrong order. I tested with multiple audio devices to be completely sure. Has anyone else noticed this, or is it an isolated issue? (The workaround is trivial since I can remap the channels with a PulseAudio config with no negative impact, but I'm still rather curious.)

Borley

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Re: Stereo audio channels swapped?
« Reply #1 on: July 12, 2022, 11:22:38 pm »
I've had to swap my headphones L/R around physically a couple of times before I finally figured out that the CM106 sound device had the channels mixed up. You're not the only one.
Blackbird C1P9S01, CPU 02CY650, 2x 8GB 2666 RAM, 1024GB M.2 SSD, AMD RX 560X, 2U heatsink, 500W SFX PSU, Debian 11

r34per

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Re: Stereo audio channels swapped?
« Reply #2 on: September 11, 2022, 01:26:50 pm »
I fought with getting the 5.1 channels right for days on fedora I just gave up and threw in a sound blaster z. All the cahnnels seem to map right with that card OOTB.
« Last Edit: September 11, 2022, 01:28:49 pm by r34per »

MPC7500

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Re: Stereo audio channels swapped?
« Reply #3 on: September 11, 2022, 03:48:25 pm »
I use the audio of the AMD GPU.

ClassicHasClass

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Re: Stereo audio channels swapped?
« Reply #4 on: September 13, 2022, 11:13:38 am »
I don't recall this being a problem on the optical output (which I feed into a Denon receiver), but maybe I'm just not discriminating enough.

Hasturtium

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Re: Stereo audio channels swapped?
« Reply #5 on: December 11, 2022, 06:03:35 pm »
In most distros there's a way to solve this by copying the /etc/pulse/default.pa file to ~/.pulse/default.pa, then appending these lines to the end of that file:
Code: [Select]
load-module module-remap-sink sink_name=reverse-stereo master=0 channels=2 master_channel_map=front-right,front-left channel_map=front-left,front-right
set-default-sink reverse-stereo
Save, exit, and execute pactl exit at the terminal to force PulseAudio to restart and enact the changes. You may need to change the master= value if the system default audio device isn't the Blackbird's built-in audio, but this worked without much hassle in Void. I am currently trying to determine the appropriate procedure for Fedora... Red Hat does things a bit differently than I'm used to. That's not bad - I just have to wrap my head around it.
« Last Edit: December 11, 2022, 06:08:32 pm by Hasturtium »

MPC7500

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Re: Stereo audio channels swapped?
« Reply #6 on: December 12, 2022, 02:09:44 pm »
If this fixes the problem, then this is worth an entry on the wiki.

Borley

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Re: Stereo audio channels swapped?
« Reply #7 on: April 07, 2023, 08:44:25 am »
All I needed to do was add

Code: [Select]
load-module module-alsa-sink device=hw:"ICUSBAUDIO7D" channel_map=right,left
in the existing /etc/pulse/default.pa
Blackbird C1P9S01, CPU 02CY650, 2x 8GB 2666 RAM, 1024GB M.2 SSD, AMD RX 560X, 2U heatsink, 500W SFX PSU, Debian 11