Extremely Low Audio Output in SteamOS 3.7.8 (Works Fine in 3.6.24)

[con-form-i-ty]

Your system information

Steam client version: 1748033199
SteamOS version: 3.7.8
Opted into Steam client beta?: No
Opted into SteamOS beta?: No
Have you checked for updates in Settings > System?: Yes

Summary

After a long-pressed the volume + button, the system volume suddenly jumped from 100% back to 1%. Since then, the audio output has been abnormal and much quieter than expected, even when set to 100%. This issue does not occur in 3.6.24, where volume levels are normal. Downgrading to 3.6.24 immediately resolves the problem. Update：Now 3.6.24 have popping sound

Steps to Reproduce

1. Boot into SteamOS 3.7.8 (desktop mode or game mode).
2. Set system volume to 100%.
3. Play any audio (YouTube, system sounds, Steam game).
4. Observe significantly reduced output volume.

Troubleshooting Tried

Checked pactl, confirmed sink volume is at 100%, not muted.
Used pavucontrol to verify no volume cap or misrouting.

[flowerdealer]

On the Legion Go S audio volume is also very low. System sounds are considerably louder than games for some reason.