On Mon, 25 Jul 2022 08:03:46 -0500 Chris Adams <linux@xxxxxxxxxxx> wrote: > I have a notebook (AMD chips) connected to a hub (via USB-C), with two > monitors hooked up to the hub (via HDMI). The monitors have built-in > speakers, and I use one monitor's speakers for default audio. I'm > running Fedora 35 MATE desktop (with Pipewire). The problem is that > which monitor's speakers are which flips around. I think this is a consequence of parallel boot. The order in which devices are discovered is non-deterministic. > Right now, the main monitor is "Renoir Radeon High Definition Audio > Controller HDMI / DisplayPort 1 Output" and the second monitor is > "<same> 4 Output". After a suspend/resume cycle though, they randomly > swap, so I have to go into Sound Preferences and change the default > output device. I would guess that these monitors have the same sound hardware? Use aplay -l to check if there are two identical devices available. It sounds (heh) like pipewire is just using the device that ends up in whatever slot it considers default. > The video side always keeps the correct monitor mapped as the correct > part of the display layout, so it seems either there's a unique ID or > something that keeps them in the right order. Is there something > similar to keep it right for audio? Not sure how video works, probably it is discriminating based on the connection. But audio is determined by alsa as it discovers sound devices. It has been a long time since I investigated this, but I think it is still possible to assign specific slots to devices using a script in /etc/modprobe.d. Something like the one at this link: https://gist.github.com/andering/801eb7fe79520036dff4a90340fac7f6 Unfortunately, my experience has been that the audio hardware on graphics devices tend to ignore this because the video starts before the other audio devices, and so always gets slot 0, the default sound device position. But, you can try assigning names to the devices as the above file demonstrates, and then assigning them positions, and then setting that position as default. Since your competing audio devices are both graphics device based, it might work. And it almost surely will work if the audio hardware on the graphics device is different for each video device. Check the layout when it is good, and when it flips, and assign your names to the devices based on that. Then, you can only try and see if it works. You might have to go down the rabbit hole to investigate further if this is irritating enough to you. e.g. ask on the alsa mailing list, web searches for people who have this exact problem and solved it, etc. _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
