Video sound is low

I connected Adafruit I2S D amp (MAX98357A) to MAiX BiT and played back video, but the sound is very low and noisy.
change the volume value, but it didn’t work.

The Adafruit board and speaker is fine.
(I checked the operation with my Raspberry Pi)

I want to play the video (bad apple) with sound.
https://maixpy.sipeed.com/en/libs/machine_vision/video.html
How can I do that ?

is it have low right sound, or just noisy?
can you play wav file normally?