maixduino board mic pinout problem

Hi,
i am trying to run standalone-sdk mic_play demo on maixduino board but with no luck, i hear only noise.

I changed I2S pins for microphone to match pins from schematics or datasheet:
http://dl.sipeed.com/MAIX/HDK/Maixduino/Maixduino-4.30/Maixduino-4.30(schematic).pdf

When i hook up mic array then it is working.