Speakers not working on Steam Deck OLED

The internal speakers don't work with chimeraOS on steam deck OLED. In game mode, the speakers are shown as auto null. In desktop mode, the only speakers listed are dummy output. I've tried reinstalling many times but the issue persists. Tried a few solutions but they all failed.

Start by reproducing the missing internal-speaker output on the Steam Deck OLED in both game mode and desktop mode. Compare the reported “auto null” and “dummy output” states, then investigate the ChimeraOS audio configuration and device detection. Done means the internal speakers are listed normally and produce sound in both modes.

Written by the indexing model from the issue text.