I think you can change the profile in PulseAudio or Pipewire. I don't know which one your distribution uses. Pipewire is the newer software.
https://www.maketecheasier.com/fix-subwoofer-not-working-in-linux/
https://wiki.archlinux.org/title/PipeWire
My 5.1 system is old and has the same chinch connector for all the speakers. I just swap the cables if something like this happens.
Thanks. That helped a lot. It gave me a good basis for some further googling.
It ended up that the Internal Clock of the hardware interface was deselected in alsamixer. Enabling it fixed the no audio issue.
For the channel remapping I tried a bunch of different config files until finally one actually managed to not be ignored. It's absurd how many separate configuration files and sound settings menus exist for linux audio and there's no guarantee the one your editing is even being used. An absolute mess IMO and it's no wonder people shy away from linux for desktop purposes.
Funny enough, despite getting the channel remapping to work, it's completely ignored unless you put pulseaudio -k into your user profile. And even now, because the remapped output device doesn't show up on boot, it has to be manually set to the default output every login.
At least I have the right channels mapped though.
I love linux but god damn is it a hot mess for the simple stuff.
Glad you were able to figure it out. Yeah, there are a lot of settings and different moving parts involved in doing audio. And the config files are all over the place. It can get nasty.
There has to be a way to make your settings and that pipeline the (system) default. Or at least change the profile that gets loaded for your specific soundcard and change and override the channel mapping so it won't load something else first.
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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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