To fix the low volume when the Xiaomi Soundbar Pro 2.0 ch is playing audio, please refer to the following steps:
The soundbar supports independent volume control. If the volume is still low after turning it up, check whether the output volume of the audio source device (mobile phone, TV, etc.) is set too low. Adjust the volume on that device.
Check if the soundbar is in Night mode. Night mode has a maximum volume of 30, which is low. To switch to Standard mode, briefly press the STANDARD button on the remote control, then increase the volume to 100 to verify the sound level.