Thank you for your support of Xiaomi products, and we apologize for the trouble you're experiencing. We have addressed this issue in the latest system update, and you can resolve the problem by performing an OTA (Over-The-Air) upgrade to the newest version.
Additionally, you can try restarting your device after the update to ensure all optimizations take effect. Charging your device to a higher battery level is recommended, as very low power conditions can occasionally affect hardware behavior like speaker output. It's also recommended to avoid using high-volume audio playback when the battery is critically low.