Optical Audio Driver (SPDIF) bugged, instantly crashes audio whenever game is launched.

[FurrFett]

I have SteamOS running on a custom built-pc as a sort of PC version of a gaming console like Playstation/Xbox and it works great except for the audio is problematic and i dont know how to fix it. I included both the system information as well as the system report because im unsue which is more helpful.

I have it connected to my Sony 4k tv through HDMI as well as i just now connected it to my audio system directly through an optical audio cable to my Logitech Z906 5.1 surround setup. It was working fine being passthrough HDMI to the system via the TV but the problem was there was a noticeable audio delay so i finally got sick of it and went and got an optical cable to bypass the TV and just output it through the SPDIF/Optical output on my computer instead.

I can set it properly in the audio settings as you can see in the image

and all the audio channels output work as they should, and when i boot the machine the intro works as does any sound effects. but the moment i launch any game the audio just crashes and will not work unless i either enter desktop mode or reboot.

i could just use the HDMI 5.1 surround option as a passthrough but again... then there is a very noticable audio delay that the only way to fix is to change my TV audio settings from passthrough-only to auto... but that then causes SteamOS not properly output 5.1 on every game. it will be set to 5.1 but its some form of stereo. the back speakers output something.. but its not proper and the decode light on the Z906 never lights up so its not properly doing surround.

i tried following a copy commands to clear the audio cache and turn off audio power saving but that has done nothing. any help or acknowledgement of it getting fixed would be greatly appreciated.

Also the reason i am using the Stable-Main beta branch thing (confusing name) is because neither the regular beta OR the stable branch work properly on a non-deck machine when you try to use things like VRR over HDMI or Surround,

Your system information

• Steam client version:
• SteamOS version: latest stable beta branch
• Opted into Steam client beta?: [Yes/No] yes
• Opted into SteamOS beta?: [Yes/No] yes
• Have you checked for updates in Settings > System?: [Yes/No] yes

Please describe your issue in as much detail as possible:

Describe what you expected should happen and what did happen.

Steps for reproducing this issue:

use optical audio connection set to 5.1 surround then launch game and audio crashes everytime

system_report.txt
system_information.txt

[FurrFett]

Okay, so to help out a bit more I tried going back to complete Stable. Fully opted out of any Beta and did a couple restarts.

On Stable (no Beta) the optical audio surround with 5.1 works properly, can test in desktop mode and launch games and it works properly but VRR does not work at all with my TV. I forgot to check about HDR.

If i upgrade to the regular Beta branch then VRR works but the audio driver is broken again. So some change between these two versions seems to be what broke it.

I will attempt the Preview branch next but i cant imagine that solves it. I’ll have to go back to Stable if i want my audio but no VRR which is going to really suck TBH.

Edit: i opted into preview but it appears to hold the same version as Beta since no update is available. So that indeed does not solve the problem.

[givname]

This sounds like a gamescope issue?
Not sure if this helps but i have my setup connected through spdif but for it to work i had to install a package called dcaenc from the aur. This works perfectly fine even in nested gamescope i dont know about gamescope-session.

[FurrFett]

This sounds like a gamescope issue? Not sure if this helps but i have my setup connected through spdif but for it to work i had to install a package called dcaenc from the aur. This works perfectly fine even in nested gamescope i dont know about gamescope-session.

Trying to solve the problem but i saw an old posting where a similar issue someone mentioned dcaenc solved their problem. But that was a long time ago and when i searched for that package it was like several years since it was updated so i dropped that avenue.

I also posted this on reddit but people were just saying using SteamOS in unintended ways would cause problems and didn’t really yet give me any solutions other than mentioning bazzite.

So i took the headache route and wiped the PC and put bazzite on it. Other than optical output not giving any surround options till i installed some kind if alsa plugins things. Its working perfectly fine now.

I got a couple games installed and am going to give it a whirl but so long as the games run as good or better i guess ill stick to bazzite.

I just hope valve can fix this problem for future users

It is Very weird though that it worked perfectly fine on the stable branch but whatever they changed right after caused optical output to completely break.

[givname]

im curios what did you install? dcaenc can provide dts via optical output and works fine for me since years (asus xonar)

[bishopdynamics]

I had the same experience: using toslink audio output for a long while on stable, moved to the latest preview because of all the new features flooding in for the Steam Box, and found the toslink no longer worked.