Redmi 15 4G / POCO M7 4G

I have a Redmi 15 4G (Global Variant). The issue is that whenever I flash any GSI ROM (such as AOSP, PixelOS, LineageOS, etc.), there is no sound when playing Facebook videos, YouTube videos, or other media. However, the surprising thing is: ✅ Calls work perfectly fine on the loudspeaker. ✅ This means there is no issue with the speaker hardware itself. I have tried various GSI ROMs, but I encounter the same problem with all of them. Does anyone know a solution to this? Is it related to the vendor, vendor_boot, dtbo, audio HAL, or Dolby? Or is there a specific fix or patch available for the Redmi 15 4G?