The sound quality is low.

[robinkam]

Thanks for sharing the Micropython example source code for demonstrating audio playing and recording on M5Stack Atom Echo. I got inspired.
However, I found the sound quality is very low, even if I used your sample wav file. It seemed the sound track was played in slow mode. Besides, in the record and play example application, I can only record for 2 seconds and play for 1 second. The quality of the playback of the sound recorded is even lower.
Do you find the same problem? Or is there any clue to avoid this issue?