XIAO NRF52840 sense board cannot recognize keywords (Voice)

Products & Technology XIAO
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1

I am trying to baby step into the Edge ML world using XIAO NRF52840,
Started working on IMU, Battery, and many things. But now I started the PDM microphone.
I want to implement keyword spotting using the XIAO, up, down, left, and right.
So I tookthe help of some good tutorials.

After a lot of struggle, I can program my XIAO module with ML code.

Now I am getting some output, but nowhere near the accuracy shown in edge impulse.
I always get noise as output.
Link to project KeywordSpotting_XIAO_NRF52840 - Dashboard - Edge Impulse

So, I wonder if my microphone is working?
So I jumped into some examples to check.

I tried,
PDMSerialPlotter from both normal and mbed environments. The result is the same; I see only noise. How can I say this?
In the serial plotter, i dont see any rise or fall when I shout at the microphone.
As it is PDM, will it behave as analog data with what I am seeing in serial?
Or am I missing something?
I also tried the MicSerialplotter code, but the result remained the same.

PDMSerialPlotter.zip (1.1 KB)
Keyword Spotting Code

nano_ble33_sense_microphone.zip (2.8 KB)

Someone please help me, Am I in right path? or missing something?

2

Resolved,

We soldered the modules on other board, but the assembly team forgot the module is having the mic and went with standard process of cleaning with IPA. I think that damaged the microphone.

I took other unsoldered module and the model worked perfectly.

Hope, I will be more careful next time.

Thank you.