ReSpeaker 2-Mics Pi HAT record in A-LAW codec have big noise

Hello all,

When I run a test with following command, everything is ok.
arecord -f cd -Dhw:0 test.wav
aplay -Dhw:0 test.wav

But when I change the audio format to A_LAW in bellow command, it come with big background noise and I barely able to hear my own voice.

pi@raspberrypi:~ $ arecord -D plughw:CARD=seeed2micvoicec -t raw -f A_LAW -r 8000 test.alaw
Recording raw data ‘test.alaw’ : A-Law, Rate 8000 Hz, Mono
pi@raspberrypi:~ $ aplay -f A_LAW -r 8000 -D plughw:CARD=seeed2micvoicec test.alaw
Playing raw data ‘test.alaw’ : A-Law, Rate 8000 Hz, Mono

My question is what I miss or need to fix this problem? I know ReSpeaker 2-Mics Pi HAT is discontinued but I real need some one to help me out. Thanks!

hardware:
Pi zero 2 W
ReSpeaker 2-Mics Pi HAT

software:
Raspberry OS Lite - buster
2-Mics Pi HAT Driver (from GitHub - respeaker/seeed-voicecard: 2 Mic Hat, 4 Mic Array, 6-Mic Circular Array Kit, and 4-Mic Linear Array Kit for Raspberry Pi)